jdk8-mips64-public/langtools: src/share/classes/com/sun/tools/javac/jvm/ClassReader.java@71f35e4b93a5 (annotated)

src/share/classes/com/sun/tools/javac/jvm/ClassReader.java@71f35e4b93a5 (annotated)

src/share/classes/com/sun/tools/javac/jvm/ClassReader.java

Wed, 23 Jan 2013 13:27:24 -0800

author: jjg
date: Wed, 23 Jan 2013 13:27:24 -0800
changeset 1521: 71f35e4b93a5
parent 1473: 31780dd06ec7
child 1563: bc456436c613
child 1570: f91144b7da75
permissions: -rw-r--r--

8006775: JSR 308: Compiler changes in JDK8
Reviewed-by: jjg
Contributed-by: mernst@cs.washington.edu, wmdietl@cs.washington.edu, mpapi@csail.mit.edu, mahmood@notnoop.com

 /*
  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */
 package com.sun.tools.javac.jvm;
 import java.io.*;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.nio.CharBuffer;
 import java.util.Arrays;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import javax.lang.model.SourceVersion;
 import javax.tools.JavaFileObject;
 import javax.tools.JavaFileManager;
 import javax.tools.JavaFileManager.Location;
 import javax.tools.StandardJavaFileManager;
 import static javax.tools.StandardLocation.*;
 import com.sun.tools.javac.comp.Annotate;
 import com.sun.tools.javac.code.*;
 import com.sun.tools.javac.code.Lint.LintCategory;
 import com.sun.tools.javac.code.Type.*;
 import com.sun.tools.javac.code.Symbol.*;
 import com.sun.tools.javac.code.Symtab;
 import com.sun.tools.javac.file.BaseFileObject;
 import com.sun.tools.javac.util.*;
 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
 import static com.sun.tools.javac.code.Flags.*;
 import static com.sun.tools.javac.code.Kinds.*;
 import static com.sun.tools.javac.code.TypeTag.CLASS;
 import static com.sun.tools.javac.jvm.ClassFile.*;
 import static com.sun.tools.javac.jvm.ClassFile.Version.*;
 import static com.sun.tools.javac.main.Option.*;
 /** This class provides operations to read a classfile into an internal
  *  representation. The internal representation is anchored in a
  *  ClassSymbol which contains in its scope symbol representations
  *  for all other definitions in the classfile. Top-level Classes themselves
  *  appear as members of the scopes of PackageSymbols.
  *
  *  <p><b>This is NOT part of any supported API.
  *  If you write code that depends on this, you do so at your own risk.
  *  This code and its internal interfaces are subject to change or
  *  deletion without notice.</b>
  */
 public class ClassReader implements Completer {
     /** The context key for the class reader. */
     protected static final Context.Key<ClassReader> classReaderKey =
         new Context.Key<ClassReader>();
     public static final int INITIAL_BUFFER_SIZE = 0x0fff0;
     Annotate annotate;
     /** Switch: verbose output.
      */
     boolean verbose;
     /** Switch: check class file for correct minor version, unrecognized
      *  attributes.
      */
     boolean checkClassFile;
     /** Switch: read constant pool and code sections. This switch is initially
      *  set to false but can be turned on from outside.
      */
     public boolean readAllOfClassFile = false;
     /** Switch: read GJ signature information.
      */
     boolean allowGenerics;
     /** Switch: read varargs attribute.
      */
     boolean allowVarargs;
     /** Switch: allow annotations.
      */
     boolean allowAnnotations;
     /** Switch: allow simplified varargs.
      */
     boolean allowSimplifiedVarargs;
    /** Lint option: warn about classfile issues
      */
     boolean lintClassfile;
     /** Switch: allow default methods
      */
     boolean allowDefaultMethods;
     /** Switch: preserve parameter names from the variable table.
      */
     public boolean saveParameterNames;
     /**
      * Switch: cache completion failures unless -XDdev is used
      */
     private boolean cacheCompletionFailure;
     /**
      * Switch: prefer source files instead of newer when both source
      * and class are available
      **/
     public boolean preferSource;
     /** The log to use for verbose output
      */
     final Log log;
     /** The symbol table. */
     Symtab syms;
     Types types;
     /** The name table. */
     final Names names;
     /** Force a completion failure on this name
      */
     final Name completionFailureName;
     /** Access to files
      */
     private final JavaFileManager fileManager;
     /** Factory for diagnostics
      */
     JCDiagnostic.Factory diagFactory;
     /** Can be reassigned from outside:
      *  the completer to be used for ".java" files. If this remains unassigned
      *  ".java" files will not be loaded.
      */
     public SourceCompleter sourceCompleter = null;
     /** A hashtable containing the encountered top-level and member classes,
      *  indexed by flat names. The table does not contain local classes.
      */
     private Map<Name,ClassSymbol> classes;
     /** A hashtable containing the encountered packages.
      */
     private Map<Name, PackageSymbol> packages;
     /** The current scope where type variables are entered.
      */
     protected Scope typevars;
     /** The path name of the class file currently being read.
      */
     protected JavaFileObject currentClassFile = null;
     /** The class or method currently being read.
      */
     protected Symbol currentOwner = null;
     /** The buffer containing the currently read class file.
      */
     byte[] buf = new byte[INITIAL_BUFFER_SIZE];
     /** The current input pointer.
      */
     protected int bp;
     /** The objects of the constant pool.
      */
     Object[] poolObj;
     /** For every constant pool entry, an index into buf where the
      *  defining section of the entry is found.
      */
     int[] poolIdx;
     /** The major version number of the class file being read. */
     int majorVersion;
     /** The minor version number of the class file being read. */
     int minorVersion;
     /** A table to hold the constant pool indices for method parameter
      * names, as given in LocalVariableTable attributes.
      */
     int[] parameterNameIndices;
     /**
      * Whether or not any parameter names have been found.
      */
     boolean haveParameterNameIndices;
     /** Set this to false every time we start reading a method
      * and are saving parameter names.  Set it to true when we see
      * MethodParameters, if it's set when we see a LocalVariableTable,
      * then we ignore the parameter names from the LVT.
      */
     boolean sawMethodParameters;
     /**
      * The set of attribute names for which warnings have been generated for the current class
      */
     Set<Name> warnedAttrs = new HashSet<Name>();
     /** Get the ClassReader instance for this invocation. */
     public static ClassReader instance(Context context) {
         ClassReader instance = context.get(classReaderKey);
         if (instance == null)
             instance = new ClassReader(context, true);
         return instance;
     }
     /** Initialize classes and packages, treating this as the definitive classreader. */
     public void init(Symtab syms) {
         init(syms, true);
     }
     /** Initialize classes and packages, optionally treating this as
      *  the definitive classreader.
      */
     private void init(Symtab syms, boolean definitive) {
         if (classes != null) return;
         if (definitive) {
             Assert.check(packages == null || packages == syms.packages);
             packages = syms.packages;
             Assert.check(classes == null || classes == syms.classes);
             classes = syms.classes;
         } else {
             packages = new HashMap<Name, PackageSymbol>();
             classes = new HashMap<Name, ClassSymbol>();
         }
         packages.put(names.empty, syms.rootPackage);
         syms.rootPackage.completer = this;
         syms.unnamedPackage.completer = this;
     }
     /** Construct a new class reader, optionally treated as the
      *  definitive classreader for this invocation.
      */
     protected ClassReader(Context context, boolean definitive) {
         if (definitive) context.put(classReaderKey, this);
         names = Names.instance(context);
         syms = Symtab.instance(context);
         types = Types.instance(context);
         fileManager = context.get(JavaFileManager.class);
         if (fileManager == null)
             throw new AssertionError("FileManager initialization error");
         diagFactory = JCDiagnostic.Factory.instance(context);
         init(syms, definitive);
         log = Log.instance(context);
         Options options = Options.instance(context);
         annotate = Annotate.instance(context);
         verbose        = options.isSet(VERBOSE);
         checkClassFile = options.isSet("-checkclassfile");
         Source source = Source.instance(context);
         allowGenerics    = source.allowGenerics();
         allowVarargs     = source.allowVarargs();
         allowAnnotations = source.allowAnnotations();
         allowSimplifiedVarargs = source.allowSimplifiedVarargs();
         allowDefaultMethods = source.allowDefaultMethods();
         saveParameterNames = options.isSet("save-parameter-names");
         cacheCompletionFailure = options.isUnset("dev");
         preferSource = "source".equals(options.get("-Xprefer"));
         completionFailureName =
             options.isSet("failcomplete")
             ? names.fromString(options.get("failcomplete"))
             : null;
         typevars = new Scope(syms.noSymbol);
         lintClassfile = Lint.instance(context).isEnabled(LintCategory.CLASSFILE);
         initAttributeReaders();
     }
     /** Add member to class unless it is synthetic.
      */
     private void enterMember(ClassSymbol c, Symbol sym) {
         if ((sym.flags_field & (SYNTHETIC|BRIDGE)) != SYNTHETIC)
             c.members_field.enter(sym);
     }
 /************************************************************************
  * Error Diagnoses
  ***********************************************************************/
     public class BadClassFile extends CompletionFailure {
         private static final long serialVersionUID = 0;
         public BadClassFile(TypeSymbol sym, JavaFileObject file, JCDiagnostic diag) {
             super(sym, createBadClassFileDiagnostic(file, diag));
         }
     }
     // where
     private JCDiagnostic createBadClassFileDiagnostic(JavaFileObject file, JCDiagnostic diag) {
         String key = (file.getKind() == JavaFileObject.Kind.SOURCE
                     ? "bad.source.file.header" : "bad.class.file.header");
         return diagFactory.fragment(key, file, diag);
     }
     public BadClassFile badClassFile(String key, Object... args) {
         return new BadClassFile (
             currentOwner.enclClass(),
             currentClassFile,
             diagFactory.fragment(key, args));
     }
 /************************************************************************
  * Buffer Access
  ***********************************************************************/
     /** Read a character.
      */
     char nextChar() {
         return (char)(((buf[bp++] & 0xFF) << 8) + (buf[bp++] & 0xFF));
     }
     /** Read a byte.
      */
     int nextByte() {
         return buf[bp++] & 0xFF;
     }
     /** Read an integer.
      */
     int nextInt() {
         return
             ((buf[bp++] & 0xFF) << 24) +
             ((buf[bp++] & 0xFF) << 16) +
             ((buf[bp++] & 0xFF) << 8) +
             (buf[bp++] & 0xFF);
     }
     /** Extract a character at position bp from buf.
      */
     char getChar(int bp) {
         return
             (char)(((buf[bp] & 0xFF) << 8) + (buf[bp+1] & 0xFF));
     }
     /** Extract an integer at position bp from buf.
      */
     int getInt(int bp) {
         return
             ((buf[bp] & 0xFF) << 24) +
             ((buf[bp+1] & 0xFF) << 16) +
             ((buf[bp+2] & 0xFF) << 8) +
             (buf[bp+3] & 0xFF);
     }
     /** Extract a long integer at position bp from buf.
      */
     long getLong(int bp) {
         DataInputStream bufin =
             new DataInputStream(new ByteArrayInputStream(buf, bp, 8));
         try {
             return bufin.readLong();
         } catch (IOException e) {
             throw new AssertionError(e);
         }
     }
     /** Extract a float at position bp from buf.
      */
     float getFloat(int bp) {
         DataInputStream bufin =
             new DataInputStream(new ByteArrayInputStream(buf, bp, 4));
         try {
             return bufin.readFloat();
         } catch (IOException e) {
             throw new AssertionError(e);
         }
     }
     /** Extract a double at position bp from buf.
      */
     double getDouble(int bp) {
         DataInputStream bufin =
             new DataInputStream(new ByteArrayInputStream(buf, bp, 8));
         try {
             return bufin.readDouble();
         } catch (IOException e) {
             throw new AssertionError(e);
         }
     }
 /************************************************************************
  * Constant Pool Access
  ***********************************************************************/
     /** Index all constant pool entries, writing their start addresses into
      *  poolIdx.
      */
     void indexPool() {
         poolIdx = new int[nextChar()];
         poolObj = new Object[poolIdx.length];
         int i = 1;
         while (i < poolIdx.length) {
             poolIdx[i++] = bp;
             byte tag = buf[bp++];
             switch (tag) {
             case CONSTANT_Utf8: case CONSTANT_Unicode: {
                 int len = nextChar();
                 bp = bp + len;
                 break;
             }
             case CONSTANT_Class:
             case CONSTANT_String:
             case CONSTANT_MethodType:
                 bp = bp + 2;
                 break;
             case CONSTANT_MethodHandle:
                 bp = bp + 3;
                 break;
             case CONSTANT_Fieldref:
             case CONSTANT_Methodref:
             case CONSTANT_InterfaceMethodref:
             case CONSTANT_NameandType:
             case CONSTANT_Integer:
             case CONSTANT_Float:
             case CONSTANT_InvokeDynamic:
                 bp = bp + 4;
                 break;
             case CONSTANT_Long:
             case CONSTANT_Double:
                 bp = bp + 8;
                 i++;
                 break;
             default:
                 throw badClassFile("bad.const.pool.tag.at",
                                    Byte.toString(tag),
                                    Integer.toString(bp -1));
             }
         }
     }
     /** Read constant pool entry at start address i, use pool as a cache.
      */
     Object readPool(int i) {
         Object result = poolObj[i];
         if (result != null) return result;
         int index = poolIdx[i];
         if (index == 0) return null;
         byte tag = buf[index];
         switch (tag) {
         case CONSTANT_Utf8:
             poolObj[i] = names.fromUtf(buf, index + 3, getChar(index + 1));
             break;
         case CONSTANT_Unicode:
             throw badClassFile("unicode.str.not.supported");
         case CONSTANT_Class:
             poolObj[i] = readClassOrType(getChar(index + 1));
             break;
         case CONSTANT_String:
             // FIXME: (footprint) do not use toString here
             poolObj[i] = readName(getChar(index + 1)).toString();
             break;
         case CONSTANT_Fieldref: {
             ClassSymbol owner = readClassSymbol(getChar(index + 1));
             NameAndType nt = (NameAndType)readPool(getChar(index + 3));
             poolObj[i] = new VarSymbol(0, nt.name, nt.uniqueType.type, owner);
             break;
         }
         case CONSTANT_Methodref:
         case CONSTANT_InterfaceMethodref: {
             ClassSymbol owner = readClassSymbol(getChar(index + 1));
             NameAndType nt = (NameAndType)readPool(getChar(index + 3));
             poolObj[i] = new MethodSymbol(0, nt.name, nt.uniqueType.type, owner);
             break;
         }
         case CONSTANT_NameandType:
             poolObj[i] = new NameAndType(
                 readName(getChar(index + 1)),
                 readType(getChar(index + 3)), types);
             break;
         case CONSTANT_Integer:
             poolObj[i] = getInt(index + 1);
             break;
         case CONSTANT_Float:
             poolObj[i] = new Float(getFloat(index + 1));
             break;
         case CONSTANT_Long:
             poolObj[i] = new Long(getLong(index + 1));
             break;
         case CONSTANT_Double:
             poolObj[i] = new Double(getDouble(index + 1));
             break;
         case CONSTANT_MethodHandle:
             skipBytes(4);
             break;
         case CONSTANT_MethodType:
             skipBytes(3);
             break;
         case CONSTANT_InvokeDynamic:
             skipBytes(5);
             break;
         default:
             throw badClassFile("bad.const.pool.tag", Byte.toString(tag));
         }
         return poolObj[i];
     }
     /** Read signature and convert to type.
      */
     Type readType(int i) {
         int index = poolIdx[i];
         return sigToType(buf, index + 3, getChar(index + 1));
     }
     /** If name is an array type or class signature, return the
      *  corresponding type; otherwise return a ClassSymbol with given name.
      */
     Object readClassOrType(int i) {
         int index =  poolIdx[i];
         int len = getChar(index + 1);
         int start = index + 3;
         Assert.check(buf[start] == '[' || buf[start + len - 1] != ';');
         // by the above assertion, the following test can be
         // simplified to (buf[start] == '[')
         return (buf[start] == '[' || buf[start + len - 1] == ';')
             ? (Object)sigToType(buf, start, len)
             : (Object)enterClass(names.fromUtf(internalize(buf, start,
                                                            len)));
     }
     /** Read signature and convert to type parameters.
      */
     List<Type> readTypeParams(int i) {
         int index = poolIdx[i];
         return sigToTypeParams(buf, index + 3, getChar(index + 1));
     }
     /** Read class entry.
      */
     ClassSymbol readClassSymbol(int i) {
         return (ClassSymbol) (readPool(i));
     }
     /** Read name.
      */
     Name readName(int i) {
         return (Name) (readPool(i));
     }
 /************************************************************************
  * Reading Types
  ***********************************************************************/
     /** The unread portion of the currently read type is
      *  signature[sigp..siglimit-1].
      */
     byte[] signature;
     int sigp;
     int siglimit;
     boolean sigEnterPhase = false;
     /** Convert signature to type, where signature is a byte array segment.
      */
     Type sigToType(byte[] sig, int offset, int len) {
         signature = sig;
         sigp = offset;
         siglimit = offset + len;
         return sigToType();
     }
     /** Convert signature to type, where signature is implicit.
      */
     Type sigToType() {
         switch ((char) signature[sigp]) {
         case 'T':
             sigp++;
             int start = sigp;
             while (signature[sigp] != ';') sigp++;
             sigp++;
             return sigEnterPhase
                 ? Type.noType
                 : findTypeVar(names.fromUtf(signature, start, sigp - 1 - start));
         case '+': {
             sigp++;
             Type t = sigToType();
             return new WildcardType(t, BoundKind.EXTENDS,
                                     syms.boundClass);
         }
         case '*':
             sigp++;
             return new WildcardType(syms.objectType, BoundKind.UNBOUND,
                                     syms.boundClass);
         case '-': {
             sigp++;
             Type t = sigToType();
             return new WildcardType(t, BoundKind.SUPER,
                                     syms.boundClass);
         }
         case 'B':
             sigp++;
             return syms.byteType;
         case 'C':
             sigp++;
             return syms.charType;
         case 'D':
             sigp++;
             return syms.doubleType;
         case 'F':
             sigp++;
             return syms.floatType;
         case 'I':
             sigp++;
             return syms.intType;
         case 'J':
             sigp++;
             return syms.longType;
         case 'L':
             {
                 // int oldsigp = sigp;
                 Type t = classSigToType();
                 if (sigp < siglimit && signature[sigp] == '.')
                     throw badClassFile("deprecated inner class signature syntax " +
                                        "(please recompile from source)");
                 /*
                 System.err.println(" decoded " +
                                    new String(signature, oldsigp, sigp-oldsigp) +
                                    " => " + t + " outer " + t.outer());
                 */
                 return t;
             }
         case 'S':
             sigp++;
             return syms.shortType;
         case 'V':
             sigp++;
             return syms.voidType;
         case 'Z':
             sigp++;
             return syms.booleanType;
         case '[':
             sigp++;
             return new ArrayType(sigToType(), syms.arrayClass);
         case '(':
             sigp++;
             List<Type> argtypes = sigToTypes(')');
             Type restype = sigToType();
             List<Type> thrown = List.nil();
             while (signature[sigp] == '^') {
                 sigp++;
                 thrown = thrown.prepend(sigToType());
             }
             return new MethodType(argtypes,
                                   restype,
                                   thrown.reverse(),
                                   syms.methodClass);
         case '<':
             typevars = typevars.dup(currentOwner);
             Type poly = new ForAll(sigToTypeParams(), sigToType());
             typevars = typevars.leave();
             return poly;
         default:
             throw badClassFile("bad.signature",
                                Convert.utf2string(signature, sigp, 10));
         }
     }
     byte[] signatureBuffer = new byte[0];
     int sbp = 0;
     /** Convert class signature to type, where signature is implicit.
      */
     Type classSigToType() {
         if (signature[sigp] != 'L')
             throw badClassFile("bad.class.signature",
                                Convert.utf2string(signature, sigp, 10));
         sigp++;
         Type outer = Type.noType;
         int startSbp = sbp;
         while (true) {
             final byte c = signature[sigp++];
             switch (c) {
             case ';': {         // end
                 ClassSymbol t = enterClass(names.fromUtf(signatureBuffer,
                                                          startSbp,
                                                          sbp - startSbp));
                 if (outer == Type.noType)
                     outer = t.erasure(types);
                 else
                     outer = new ClassType(outer, List.<Type>nil(), t);
                 sbp = startSbp;
                 return outer;
             }
             case '<':           // generic arguments
                 ClassSymbol t = enterClass(names.fromUtf(signatureBuffer,
                                                          startSbp,
                                                          sbp - startSbp));
                 outer = new ClassType(outer, sigToTypes('>'), t) {
                         boolean completed = false;
                         @Override
                         public Type getEnclosingType() {
                             if (!completed) {
                                 completed = true;
                                 tsym.complete();
                                 Type enclosingType = tsym.type.getEnclosingType();
                                 if (enclosingType != Type.noType) {
                                     List<Type> typeArgs =
                                         super.getEnclosingType().allparams();
                                     List<Type> typeParams =
                                         enclosingType.allparams();
                                     if (typeParams.length() != typeArgs.length()) {
                                         // no "rare" types
                                         super.setEnclosingType(types.erasure(enclosingType));
                                     } else {
                                         super.setEnclosingType(types.subst(enclosingType,
                                                                            typeParams,
                                                                            typeArgs));
                                     }
                                 } else {
                                     super.setEnclosingType(Type.noType);
                                 }
                             }
                             return super.getEnclosingType();
                         }
                         @Override
                         public void setEnclosingType(Type outer) {
                             throw new UnsupportedOperationException();
                         }
                     };
                 switch (signature[sigp++]) {
                 case ';':
                     if (sigp < signature.length && signature[sigp] == '.') {
                         // support old-style GJC signatures
                         // The signature produced was
                         // Lfoo/Outer<Lfoo/X;>;.Lfoo/Outer$Inner<Lfoo/Y;>;
                         // rather than say
                         // Lfoo/Outer<Lfoo/X;>.Inner<Lfoo/Y;>;
                         // so we skip past ".Lfoo/Outer$"
                         sigp += (sbp - startSbp) + // "foo/Outer"
 ;  // ".L" and "$"
                         signatureBuffer[sbp++] = (byte)'$';
                         break;
                     } else {
                         sbp = startSbp;
                         return outer;
                     }
                 case '.':
                     signatureBuffer[sbp++] = (byte)'$';
                     break;
                 default:
                     throw new AssertionError(signature[sigp-1]);
                 }
                 continue;
             case '.':
                 signatureBuffer[sbp++] = (byte)'$';
                 continue;
             case '/':
                 signatureBuffer[sbp++] = (byte)'.';
                 continue;
             default:
                 signatureBuffer[sbp++] = c;
                 continue;
             }
         }
     }
     /** Convert (implicit) signature to list of types
      *  until `terminator' is encountered.
      */
     List<Type> sigToTypes(char terminator) {
         List<Type> head = List.of(null);
         List<Type> tail = head;
         while (signature[sigp] != terminator)
             tail = tail.setTail(List.of(sigToType()));
         sigp++;
         return head.tail;
     }
     /** Convert signature to type parameters, where signature is a byte
      *  array segment.
      */
     List<Type> sigToTypeParams(byte[] sig, int offset, int len) {
         signature = sig;
         sigp = offset;
         siglimit = offset + len;
         return sigToTypeParams();
     }
     /** Convert signature to type parameters, where signature is implicit.
      */
     List<Type> sigToTypeParams() {
         List<Type> tvars = List.nil();
         if (signature[sigp] == '<') {
             sigp++;
             int start = sigp;
             sigEnterPhase = true;
             while (signature[sigp] != '>')
                 tvars = tvars.prepend(sigToTypeParam());
             sigEnterPhase = false;
             sigp = start;
             while (signature[sigp] != '>')
                 sigToTypeParam();
             sigp++;
         }
         return tvars.reverse();
     }
     /** Convert (implicit) signature to type parameter.
      */
     Type sigToTypeParam() {
         int start = sigp;
         while (signature[sigp] != ':') sigp++;
         Name name = names.fromUtf(signature, start, sigp - start);
         TypeVar tvar;
         if (sigEnterPhase) {
             tvar = new TypeVar(name, currentOwner, syms.botType);
             typevars.enter(tvar.tsym);
         } else {
             tvar = (TypeVar)findTypeVar(name);
         }
         List<Type> bounds = List.nil();
         boolean allInterfaces = false;
         if (signature[sigp] == ':' && signature[sigp+1] == ':') {
             sigp++;
             allInterfaces = true;
         }
         while (signature[sigp] == ':') {
             sigp++;
             bounds = bounds.prepend(sigToType());
         }
         if (!sigEnterPhase) {
             types.setBounds(tvar, bounds.reverse(), allInterfaces);
         }
         return tvar;
     }
     /** Find type variable with given name in `typevars' scope.
      */
     Type findTypeVar(Name name) {
         Scope.Entry e = typevars.lookup(name);
         if (e.scope != null) {
             return e.sym.type;
         } else {
             if (readingClassAttr) {
                 // While reading the class attribute, the supertypes
                 // might refer to a type variable from an enclosing element
                 // (method or class).
                 // If the type variable is defined in the enclosing class,
                 // we can actually find it in
                 // currentOwner.owner.type.getTypeArguments()
                 // However, until we have read the enclosing method attribute
                 // we don't know for sure if this owner is correct.  It could
                 // be a method and there is no way to tell before reading the
                 // enclosing method attribute.
                 TypeVar t = new TypeVar(name, currentOwner, syms.botType);
                 missingTypeVariables = missingTypeVariables.prepend(t);
                 // System.err.println("Missing type var " + name);
                 return t;
             }
             throw badClassFile("undecl.type.var", name);
         }
     }
 /************************************************************************
  * Reading Attributes
  ***********************************************************************/
     protected enum AttributeKind { CLASS, MEMBER };
     protected abstract class AttributeReader {
         protected AttributeReader(Name name, ClassFile.Version version, Set<AttributeKind> kinds) {
             this.name = name;
             this.version = version;
             this.kinds = kinds;
         }
         protected boolean accepts(AttributeKind kind) {
             if (kinds.contains(kind)) {
                 if (majorVersion > version.major || (majorVersion == version.major && minorVersion >= version.minor))
                     return true;
                 if (lintClassfile && !warnedAttrs.contains(name)) {
                     JavaFileObject prev = log.useSource(currentClassFile);
                     try {
                         log.warning(LintCategory.CLASSFILE, (DiagnosticPosition) null, "future.attr",
                                 name, version.major, version.minor, majorVersion, minorVersion);
                     } finally {
                         log.useSource(prev);
                     }
                     warnedAttrs.add(name);
                 }
             }
             return false;
         }
         protected abstract void read(Symbol sym, int attrLen);
         protected final Name name;
         protected final ClassFile.Version version;
         protected final Set<AttributeKind> kinds;
     }
     protected Set<AttributeKind> CLASS_ATTRIBUTE =
             EnumSet.of(AttributeKind.CLASS);
     protected Set<AttributeKind> MEMBER_ATTRIBUTE =
             EnumSet.of(AttributeKind.MEMBER);
     protected Set<AttributeKind> CLASS_OR_MEMBER_ATTRIBUTE =
             EnumSet.of(AttributeKind.CLASS, AttributeKind.MEMBER);
     protected Map<Name, AttributeReader> attributeReaders = new HashMap<Name, AttributeReader>();
     private void initAttributeReaders() {
         AttributeReader[] readers = {
             // v45.3 attributes
             new AttributeReader(names.Code, V45_3, MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     if (readAllOfClassFile || saveParameterNames)
                         ((MethodSymbol)sym).code = readCode(sym);
                     else
                         bp = bp + attrLen;
                 }
             },
             new AttributeReader(names.ConstantValue, V45_3, MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     Object v = readPool(nextChar());
                     // Ignore ConstantValue attribute if field not final.
                     if ((sym.flags() & FINAL) != 0)
                         ((VarSymbol) sym).setData(v);
                 }
             },
             new AttributeReader(names.Deprecated, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     sym.flags_field |= DEPRECATED;
                 }
             },
             new AttributeReader(names.Exceptions, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     int nexceptions = nextChar();
                     List<Type> thrown = List.nil();
                     for (int j = 0; j < nexceptions; j++)
                         thrown = thrown.prepend(readClassSymbol(nextChar()).type);
                     if (sym.type.getThrownTypes().isEmpty())
                         sym.type.asMethodType().thrown = thrown.reverse();
                 }
             },
             new AttributeReader(names.InnerClasses, V45_3, CLASS_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     ClassSymbol c = (ClassSymbol) sym;
                     readInnerClasses(c);
                 }
             },
             new AttributeReader(names.LocalVariableTable, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     int newbp = bp + attrLen;
                     if (saveParameterNames && !sawMethodParameters) {
                         // Pick up parameter names from the variable table.
                         // Parameter names are not explicitly identified as such,
                         // but all parameter name entries in the LocalVariableTable
                         // have a start_pc of 0.  Therefore, we record the name
                         // indicies of all slots with a start_pc of zero in the
                         // parameterNameIndicies array.
                         // Note that this implicitly honors the JVMS spec that
                         // there may be more than one LocalVariableTable, and that
                         // there is no specified ordering for the entries.
                         int numEntries = nextChar();
                         for (int i = 0; i < numEntries; i++) {
                             int start_pc = nextChar();
                             int length = nextChar();
                             int nameIndex = nextChar();
                             int sigIndex = nextChar();
                             int register = nextChar();
                             if (start_pc == 0) {
                                 // ensure array large enough
                                 if (register >= parameterNameIndices.length) {
                                     int newSize = Math.max(register, parameterNameIndices.length + 8);
                                     parameterNameIndices =
                                             Arrays.copyOf(parameterNameIndices, newSize);
                                 }
                                 parameterNameIndices[register] = nameIndex;
                                 haveParameterNameIndices = true;
                             }
                         }
                     }
                     bp = newbp;
                 }
             },
             new AttributeReader(names.MethodParameters, V52, MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrlen) {
                     int newbp = bp + attrlen;
                     if (saveParameterNames) {
                         sawMethodParameters = true;
                         int numEntries = nextByte();
                         parameterNameIndices = new int[numEntries];
                         haveParameterNameIndices = true;
                         for (int i = 0; i < numEntries; i++) {
                             int nameIndex = nextChar();
                             int flags = nextInt();
                             parameterNameIndices[i] = nameIndex;
                         }
                     }
                     bp = newbp;
                 }
             },
             new AttributeReader(names.SourceFile, V45_3, CLASS_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     ClassSymbol c = (ClassSymbol) sym;
                     Name n = readName(nextChar());
                     c.sourcefile = new SourceFileObject(n, c.flatname);
                     // If the class is a toplevel class, originating from a Java source file,
                     // but the class name does not match the file name, then it is
                     // an auxiliary class.
                     String sn = n.toString();
                     if (c.owner.kind == Kinds.PCK &&
                         sn.endsWith(".java") &&
                         !sn.equals(c.name.toString()+".java")) {
                         c.flags_field |= AUXILIARY;
                     }
                 }
             },
             new AttributeReader(names.Synthetic, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     // bridge methods are visible when generics not enabled
                     if (allowGenerics || (sym.flags_field & BRIDGE) == 0)
                         sym.flags_field |= SYNTHETIC;
                 }
             },
             // standard v49 attributes
             new AttributeReader(names.EnclosingMethod, V49, CLASS_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     int newbp = bp + attrLen;
                     readEnclosingMethodAttr(sym);
                     bp = newbp;
                 }
             },
             new AttributeReader(names.Signature, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 @Override
                 protected boolean accepts(AttributeKind kind) {
                     return super.accepts(kind) && allowGenerics;
                 }
                 protected void read(Symbol sym, int attrLen) {
                     if (sym.kind == TYP) {
                         ClassSymbol c = (ClassSymbol) sym;
                         readingClassAttr = true;
                         try {
                             ClassType ct1 = (ClassType)c.type;
                             Assert.check(c == currentOwner);
                             ct1.typarams_field = readTypeParams(nextChar());
                             ct1.supertype_field = sigToType();
                             ListBuffer<Type> is = new ListBuffer<Type>();
                             while (sigp != siglimit) is.append(sigToType());
                             ct1.interfaces_field = is.toList();
                         } finally {
                             readingClassAttr = false;
                         }
                     } else {
                         List<Type> thrown = sym.type.getThrownTypes();
                         sym.type = readType(nextChar());
                         //- System.err.println(" # " + sym.type);
                         if (sym.kind == MTH && sym.type.getThrownTypes().isEmpty())
                             sym.type.asMethodType().thrown = thrown;
                     }
                 }
             },
             // v49 annotation attributes
             new AttributeReader(names.AnnotationDefault, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachAnnotationDefault(sym);
                 }
             },
             new AttributeReader(names.RuntimeInvisibleAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachAnnotations(sym);
                 }
             },
             new AttributeReader(names.RuntimeInvisibleParameterAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachParameterAnnotations(sym);
                 }
             },
             new AttributeReader(names.RuntimeVisibleAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachAnnotations(sym);
                 }
             },
             new AttributeReader(names.RuntimeVisibleParameterAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachParameterAnnotations(sym);
                 }
             },
             // additional "legacy" v49 attributes, superceded by flags
             new AttributeReader(names.Annotation, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     if (allowAnnotations)
                         sym.flags_field |= ANNOTATION;
                 }
             },
             new AttributeReader(names.Bridge, V49, MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     sym.flags_field |= BRIDGE;
                     if (!allowGenerics)
                         sym.flags_field &= ~SYNTHETIC;
                 }
             },
             new AttributeReader(names.Enum, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     sym.flags_field |= ENUM;
                 }
             },
             new AttributeReader(names.Varargs, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     if (allowVarargs)
                         sym.flags_field |= VARARGS;
                 }
             },
             new AttributeReader(names.RuntimeVisibleTypeAnnotations, V52, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachTypeAnnotations(sym);
                 }
             },
             new AttributeReader(names.RuntimeInvisibleTypeAnnotations, V52, CLASS_OR_MEMBER_ATTRIBUTE) {
                 protected void read(Symbol sym, int attrLen) {
                     attachTypeAnnotations(sym);
                 }
             },
             // The following attributes for a Code attribute are not currently handled
             // StackMapTable
             // SourceDebugExtension
             // LineNumberTable
             // LocalVariableTypeTable
         };
         for (AttributeReader r: readers)
             attributeReaders.put(r.name, r);
     }
     /** Report unrecognized attribute.
      */
     void unrecognized(Name attrName) {
         if (checkClassFile)
             printCCF("ccf.unrecognized.attribute", attrName);
     }
     protected void readEnclosingMethodAttr(Symbol sym) {
         // sym is a nested class with an "Enclosing Method" attribute
         // remove sym from it's current owners scope and place it in
         // the scope specified by the attribute
         sym.owner.members().remove(sym);
         ClassSymbol self = (ClassSymbol)sym;
         ClassSymbol c = readClassSymbol(nextChar());
         NameAndType nt = (NameAndType)readPool(nextChar());
         if (c.members_field == null)
             throw badClassFile("bad.enclosing.class", self, c);
         MethodSymbol m = findMethod(nt, c.members_field, self.flags());
         if (nt != null && m == null)
             throw badClassFile("bad.enclosing.method", self);
         self.name = simpleBinaryName(self.flatname, c.flatname) ;
         self.owner = m != null ? m : c;
         if (self.name.isEmpty())
             self.fullname = names.empty;
         else
             self.fullname = ClassSymbol.formFullName(self.name, self.owner);
         if (m != null) {
             ((ClassType)sym.type).setEnclosingType(m.type);
         } else if ((self.flags_field & STATIC) == 0) {
             ((ClassType)sym.type).setEnclosingType(c.type);
         } else {
             ((ClassType)sym.type).setEnclosingType(Type.noType);
         }
         enterTypevars(self);
         if (!missingTypeVariables.isEmpty()) {
             ListBuffer<Type> typeVars =  new ListBuffer<Type>();
             for (Type typevar : missingTypeVariables) {
                 typeVars.append(findTypeVar(typevar.tsym.name));
             }
             foundTypeVariables = typeVars.toList();
         } else {
             foundTypeVariables = List.nil();
         }
     }
     // See java.lang.Class
     private Name simpleBinaryName(Name self, Name enclosing) {
         String simpleBinaryName = self.toString().substring(enclosing.toString().length());
         if (simpleBinaryName.length() < 1 || simpleBinaryName.charAt(0) != '$')
             throw badClassFile("bad.enclosing.method", self);
         int index = 1;
         while (index < simpleBinaryName.length() &&
                isAsciiDigit(simpleBinaryName.charAt(index)))
             index++;
         return names.fromString(simpleBinaryName.substring(index));
     }
     private MethodSymbol findMethod(NameAndType nt, Scope scope, long flags) {
         if (nt == null)
             return null;
         MethodType type = nt.uniqueType.type.asMethodType();
         for (Scope.Entry e = scope.lookup(nt.name); e.scope != null; e = e.next())
             if (e.sym.kind == MTH && isSameBinaryType(e.sym.type.asMethodType(), type))
                 return (MethodSymbol)e.sym;
         if (nt.name != names.init)
             // not a constructor
             return null;
         if ((flags & INTERFACE) != 0)
             // no enclosing instance
             return null;
         if (nt.uniqueType.type.getParameterTypes().isEmpty())
             // no parameters
             return null;
         // A constructor of an inner class.
         // Remove the first argument (the enclosing instance)
         nt.setType(new MethodType(nt.uniqueType.type.getParameterTypes().tail,
                                  nt.uniqueType.type.getReturnType(),
                                  nt.uniqueType.type.getThrownTypes(),
                                  syms.methodClass));
         // Try searching again
         return findMethod(nt, scope, flags);
     }
     /** Similar to Types.isSameType but avoids completion */
     private boolean isSameBinaryType(MethodType mt1, MethodType mt2) {
         List<Type> types1 = types.erasure(mt1.getParameterTypes())
             .prepend(types.erasure(mt1.getReturnType()));
         List<Type> types2 = mt2.getParameterTypes().prepend(mt2.getReturnType());
         while (!types1.isEmpty() && !types2.isEmpty()) {
             if (types1.head.tsym != types2.head.tsym)
                 return false;
             types1 = types1.tail;
             types2 = types2.tail;
         }
         return types1.isEmpty() && types2.isEmpty();
     }
     /**
      * Character.isDigit answers <tt>true</tt> to some non-ascii
      * digits.  This one does not.  <b>copied from java.lang.Class</b>
      */
     private static boolean isAsciiDigit(char c) {
         return '0' <= c && c <= '9';
     }
     /** Read member attributes.
      */
     void readMemberAttrs(Symbol sym) {
         readAttrs(sym, AttributeKind.MEMBER);
     }
     void readAttrs(Symbol sym, AttributeKind kind) {
         char ac = nextChar();
         for (int i = 0; i < ac; i++) {
             Name attrName = readName(nextChar());
             int attrLen = nextInt();
             AttributeReader r = attributeReaders.get(attrName);
             if (r != null && r.accepts(kind))
                 r.read(sym, attrLen);
             else  {
                 unrecognized(attrName);
                 bp = bp + attrLen;
             }
         }
     }
     private boolean readingClassAttr = false;
     private List<Type> missingTypeVariables = List.nil();
     private List<Type> foundTypeVariables = List.nil();
     /** Read class attributes.
      */
     void readClassAttrs(ClassSymbol c) {
         readAttrs(c, AttributeKind.CLASS);
     }
     /** Read code block.
      */
     Code readCode(Symbol owner) {
         nextChar(); // max_stack
         nextChar(); // max_locals
         final int  code_length = nextInt();
         bp += code_length;
         final char exception_table_length = nextChar();
         bp += exception_table_length * 8;
         readMemberAttrs(owner);
         return null;
     }
 /************************************************************************
  * Reading Java-language annotations
  ***********************************************************************/
     /** Attach annotations.
      */
     void attachAnnotations(final Symbol sym) {
         int numAttributes = nextChar();
         if (numAttributes != 0) {
             ListBuffer<CompoundAnnotationProxy> proxies =
                 new ListBuffer<CompoundAnnotationProxy>();
             for (int i = 0; i<numAttributes; i++) {
                 CompoundAnnotationProxy proxy = readCompoundAnnotation();
                 if (proxy.type.tsym == syms.proprietaryType.tsym)
                     sym.flags_field |= PROPRIETARY;
                 else
                     proxies.append(proxy);
             }
             annotate.normal(new AnnotationCompleter(sym, proxies.toList()));
         }
     }
     /** Attach parameter annotations.
      */
     void attachParameterAnnotations(final Symbol method) {
         final MethodSymbol meth = (MethodSymbol)method;
         int numParameters = buf[bp++] & 0xFF;
         List<VarSymbol> parameters = meth.params();
         int pnum = 0;
         while (parameters.tail != null) {
             attachAnnotations(parameters.head);
             parameters = parameters.tail;
             pnum++;
         }
         if (pnum != numParameters) {
             throw badClassFile("bad.runtime.invisible.param.annotations", meth);
         }
     }
     void attachTypeAnnotations(final Symbol sym) {
         int numAttributes = nextChar();
         if (numAttributes != 0) {
             ListBuffer<TypeAnnotationProxy> proxies =
                 ListBuffer.lb();
             for (int i = 0; i < numAttributes; i++)
                 proxies.append(readTypeAnnotation());
             annotate.normal(new TypeAnnotationCompleter(sym, proxies.toList()));
         }
     }
     /** Attach the default value for an annotation element.
      */
     void attachAnnotationDefault(final Symbol sym) {
         final MethodSymbol meth = (MethodSymbol)sym; // only on methods
         final Attribute value = readAttributeValue();
         // The default value is set later during annotation. It might
         // be the case that the Symbol sym is annotated _after_ the
         // repeating instances that depend on this default value,
         // because of this we set an interim value that tells us this
         // element (most likely) has a default.
         //
         // Set interim value for now, reset just before we do this
         // properly at annotate time.
         meth.defaultValue = value;
         annotate.normal(new AnnotationDefaultCompleter(meth, value));
     }
     Type readTypeOrClassSymbol(int i) {
         // support preliminary jsr175-format class files
         if (buf[poolIdx[i]] == CONSTANT_Class)
             return readClassSymbol(i).type;
         return readType(i);
     }
     Type readEnumType(int i) {
         // support preliminary jsr175-format class files
         int index = poolIdx[i];
         int length = getChar(index + 1);
         if (buf[index + length + 2] != ';')
             return enterClass(readName(i)).type;
         return readType(i);
     }
     CompoundAnnotationProxy readCompoundAnnotation() {
         Type t = readTypeOrClassSymbol(nextChar());
         int numFields = nextChar();
         ListBuffer<Pair<Name,Attribute>> pairs =
             new ListBuffer<Pair<Name,Attribute>>();
         for (int i=0; i<numFields; i++) {
             Name name = readName(nextChar());
             Attribute value = readAttributeValue();
             pairs.append(new Pair<Name,Attribute>(name, value));
         }
         return new CompoundAnnotationProxy(t, pairs.toList());
     }
     TypeAnnotationProxy readTypeAnnotation() {
         TypeAnnotationPosition position = readPosition();
         CompoundAnnotationProxy proxy = readCompoundAnnotation();
         return new TypeAnnotationProxy(proxy, position);
     }
     TypeAnnotationPosition readPosition() {
         int tag = nextByte(); // TargetType tag is a byte
         if (!TargetType.isValidTargetTypeValue(tag))
             throw this.badClassFile("bad.type.annotation.value", String.format("0x%02X", tag));
         TypeAnnotationPosition position = new TypeAnnotationPosition();
         TargetType type = TargetType.fromTargetTypeValue(tag);
         position.type = type;
         switch (type) {
         // type cast
         case CAST:
         // instanceof
         case INSTANCEOF:
         // new expression
         case NEW:
             position.offset = nextChar();
             break;
         // local variable
         case LOCAL_VARIABLE:
         // resource variable
         case RESOURCE_VARIABLE:
             int table_length = nextChar();
             position.lvarOffset = new int[table_length];
             position.lvarLength = new int[table_length];
             position.lvarIndex = new int[table_length];
             for (int i = 0; i < table_length; ++i) {
                 position.lvarOffset[i] = nextChar();
                 position.lvarLength[i] = nextChar();
                 position.lvarIndex[i] = nextChar();
             }
             break;
         // exception parameter
         case EXCEPTION_PARAMETER:
             position.exception_index = nextByte();
             break;
         // method receiver
         case METHOD_RECEIVER:
             // Do nothing
             break;
         // type parameter
         case CLASS_TYPE_PARAMETER:
         case METHOD_TYPE_PARAMETER:
             position.parameter_index = nextByte();
             break;
         // type parameter bound
         case CLASS_TYPE_PARAMETER_BOUND:
         case METHOD_TYPE_PARAMETER_BOUND:
             position.parameter_index = nextByte();
             position.bound_index = nextByte();
             break;
         // class extends or implements clause
         case CLASS_EXTENDS:
             position.type_index = nextChar();
             break;
         // throws
         case THROWS:
             position.type_index = nextChar();
             break;
         // method parameter
         case METHOD_FORMAL_PARAMETER:
             position.parameter_index = nextByte();
             break;
         // method/constructor/reference type argument
         case CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT:
         case METHOD_INVOCATION_TYPE_ARGUMENT:
         case METHOD_REFERENCE_TYPE_ARGUMENT:
             position.offset = nextChar();
             position.type_index = nextByte();
             break;
         // We don't need to worry about these
         case METHOD_RETURN:
         case FIELD:
             break;
         // lambda formal parameter
         case LAMBDA_FORMAL_PARAMETER:
             position.parameter_index = nextByte();
             break;
         case UNKNOWN:
             throw new AssertionError("jvm.ClassReader: UNKNOWN target type should never occur!");
         default:
             throw new AssertionError("jvm.ClassReader: Unknown target type for position: " + position);
         }
         { // See whether there is location info and read it
             int len = nextByte();
             ListBuffer<Integer> loc = ListBuffer.lb();
             for (int i = 0; i < len * TypeAnnotationPosition.TypePathEntry.bytesPerEntry; ++i)
                 loc = loc.append(nextByte());
             position.location = TypeAnnotationPosition.getTypePathFromBinary(loc.toList());
         }
         return position;
     }
     Attribute readAttributeValue() {
         char c = (char) buf[bp++];
         switch (c) {
         case 'B':
             return new Attribute.Constant(syms.byteType, readPool(nextChar()));
         case 'C':
             return new Attribute.Constant(syms.charType, readPool(nextChar()));
         case 'D':
             return new Attribute.Constant(syms.doubleType, readPool(nextChar()));
         case 'F':
             return new Attribute.Constant(syms.floatType, readPool(nextChar()));
         case 'I':
             return new Attribute.Constant(syms.intType, readPool(nextChar()));
         case 'J':
             return new Attribute.Constant(syms.longType, readPool(nextChar()));
         case 'S':
             return new Attribute.Constant(syms.shortType, readPool(nextChar()));
         case 'Z':
             return new Attribute.Constant(syms.booleanType, readPool(nextChar()));
         case 's':
             return new Attribute.Constant(syms.stringType, readPool(nextChar()).toString());
         case 'e':
             return new EnumAttributeProxy(readEnumType(nextChar()), readName(nextChar()));
         case 'c':
             return new Attribute.Class(types, readTypeOrClassSymbol(nextChar()));
         case '[': {
             int n = nextChar();
             ListBuffer<Attribute> l = new ListBuffer<Attribute>();
             for (int i=0; i<n; i++)
                 l.append(readAttributeValue());
             return new ArrayAttributeProxy(l.toList());
         }
         case '@':
             return readCompoundAnnotation();
         default:
             throw new AssertionError("unknown annotation tag '" + c + "'");
         }
     }
     interface ProxyVisitor extends Attribute.Visitor {
         void visitEnumAttributeProxy(EnumAttributeProxy proxy);
         void visitArrayAttributeProxy(ArrayAttributeProxy proxy);
         void visitCompoundAnnotationProxy(CompoundAnnotationProxy proxy);
     }
     static class EnumAttributeProxy extends Attribute {
         Type enumType;
         Name enumerator;
         public EnumAttributeProxy(Type enumType, Name enumerator) {
             super(null);
             this.enumType = enumType;
             this.enumerator = enumerator;
         }
         public void accept(Visitor v) { ((ProxyVisitor)v).visitEnumAttributeProxy(this); }
         @Override
         public String toString() {
             return "/*proxy enum*/" + enumType + "." + enumerator;
         }
     }
     static class ArrayAttributeProxy extends Attribute {
         List<Attribute> values;
         ArrayAttributeProxy(List<Attribute> values) {
             super(null);
             this.values = values;
         }
         public void accept(Visitor v) { ((ProxyVisitor)v).visitArrayAttributeProxy(this); }
         @Override
         public String toString() {
             return "{" + values + "}";
         }
     }
     /** A temporary proxy representing a compound attribute.
      */
     static class CompoundAnnotationProxy extends Attribute {
         final List<Pair<Name,Attribute>> values;
         public CompoundAnnotationProxy(Type type,
                                       List<Pair<Name,Attribute>> values) {
             super(type);
             this.values = values;
         }
         public void accept(Visitor v) { ((ProxyVisitor)v).visitCompoundAnnotationProxy(this); }
         @Override
         public String toString() {
             StringBuilder buf = new StringBuilder();
             buf.append("@");
             buf.append(type.tsym.getQualifiedName());
             buf.append("/*proxy*/{");
             boolean first = true;
             for (List<Pair<Name,Attribute>> v = values;
                  v.nonEmpty(); v = v.tail) {
                 Pair<Name,Attribute> value = v.head;
                 if (!first) buf.append(",");
                 first = false;
                 buf.append(value.fst);
                 buf.append("=");
                 buf.append(value.snd);
             }
             buf.append("}");
             return buf.toString();
         }
     }
     /** A temporary proxy representing a type annotation.
      */
     static class TypeAnnotationProxy {
         final CompoundAnnotationProxy compound;
         final TypeAnnotationPosition position;
         public TypeAnnotationProxy(CompoundAnnotationProxy compound,
                 TypeAnnotationPosition position) {
             this.compound = compound;
             this.position = position;
         }
     }
     class AnnotationDeproxy implements ProxyVisitor {
         private ClassSymbol requestingOwner = currentOwner.kind == MTH
             ? currentOwner.enclClass() : (ClassSymbol)currentOwner;
         List<Attribute.Compound> deproxyCompoundList(List<CompoundAnnotationProxy> pl) {
             // also must fill in types!!!!
             ListBuffer<Attribute.Compound> buf =
                 new ListBuffer<Attribute.Compound>();
             for (List<CompoundAnnotationProxy> l = pl; l.nonEmpty(); l=l.tail) {
                 buf.append(deproxyCompound(l.head));
             }
             return buf.toList();
         }
         Attribute.Compound deproxyCompound(CompoundAnnotationProxy a) {
             ListBuffer<Pair<Symbol.MethodSymbol,Attribute>> buf =
                 new ListBuffer<Pair<Symbol.MethodSymbol,Attribute>>();
             for (List<Pair<Name,Attribute>> l = a.values;
                  l.nonEmpty();
                  l = l.tail) {
                 MethodSymbol meth = findAccessMethod(a.type, l.head.fst);
                 buf.append(new Pair<Symbol.MethodSymbol,Attribute>
                            (meth, deproxy(meth.type.getReturnType(), l.head.snd)));
             }
             return new Attribute.Compound(a.type, buf.toList());
         }
         MethodSymbol findAccessMethod(Type container, Name name) {
             CompletionFailure failure = null;
             try {
                 for (Scope.Entry e = container.tsym.members().lookup(name);
                      e.scope != null;
                      e = e.next()) {
                     Symbol sym = e.sym;
                     if (sym.kind == MTH && sym.type.getParameterTypes().length() == 0)
                         return (MethodSymbol) sym;
                 }
             } catch (CompletionFailure ex) {
                 failure = ex;
             }
             // The method wasn't found: emit a warning and recover
             JavaFileObject prevSource = log.useSource(requestingOwner.classfile);
             try {
                 if (failure == null) {
                     log.warning("annotation.method.not.found",
                                 container,
                                 name);
                 } else {
                     log.warning("annotation.method.not.found.reason",
                                 container,
                                 name,
                                 failure.getDetailValue());//diagnostic, if present
                 }
             } finally {
                 log.useSource(prevSource);
             }
             // Construct a new method type and symbol.  Use bottom
             // type (typeof null) as return type because this type is
             // a subtype of all reference types and can be converted
             // to primitive types by unboxing.
             MethodType mt = new MethodType(List.<Type>nil(),
                                            syms.botType,
                                            List.<Type>nil(),
                                            syms.methodClass);
             return new MethodSymbol(PUBLIC | ABSTRACT, name, mt, container.tsym);
         }
         Attribute result;
         Type type;
         Attribute deproxy(Type t, Attribute a) {
             Type oldType = type;
             try {
                 type = t;
                 a.accept(this);
                 return result;
             } finally {
                 type = oldType;
             }
         }
         // implement Attribute.Visitor below
         public void visitConstant(Attribute.Constant value) {
             // assert value.type == type;
             result = value;
         }
         public void visitClass(Attribute.Class clazz) {
             result = clazz;
         }
         public void visitEnum(Attribute.Enum e) {
             throw new AssertionError(); // shouldn't happen
         }
         public void visitCompound(Attribute.Compound compound) {
             throw new AssertionError(); // shouldn't happen
         }
         public void visitArray(Attribute.Array array) {
             throw new AssertionError(); // shouldn't happen
         }
         public void visitError(Attribute.Error e) {
             throw new AssertionError(); // shouldn't happen
         }
         public void visitEnumAttributeProxy(EnumAttributeProxy proxy) {
             // type.tsym.flatName() should == proxy.enumFlatName
             TypeSymbol enumTypeSym = proxy.enumType.tsym;
             VarSymbol enumerator = null;
             CompletionFailure failure = null;
             try {
                 for (Scope.Entry e = enumTypeSym.members().lookup(proxy.enumerator);
                      e.scope != null;
                      e = e.next()) {
                     if (e.sym.kind == VAR) {
                         enumerator = (VarSymbol)e.sym;
                         break;
                     }
                 }
             }
             catch (CompletionFailure ex) {
                 failure = ex;
             }
             if (enumerator == null) {
                 if (failure != null) {
                     log.warning("unknown.enum.constant.reason",
                               currentClassFile, enumTypeSym, proxy.enumerator,
                               failure.getDiagnostic());
                 } else {
                     log.warning("unknown.enum.constant",
                               currentClassFile, enumTypeSym, proxy.enumerator);
                 }
                 result = new Attribute.Enum(enumTypeSym.type,
                         new VarSymbol(0, proxy.enumerator, syms.botType, enumTypeSym));
             } else {
                 result = new Attribute.Enum(enumTypeSym.type, enumerator);
             }
         }
         public void visitArrayAttributeProxy(ArrayAttributeProxy proxy) {
             int length = proxy.values.length();
             Attribute[] ats = new Attribute[length];
             Type elemtype = types.elemtype(type);
             int i = 0;
             for (List<Attribute> p = proxy.values; p.nonEmpty(); p = p.tail) {
                 ats[i++] = deproxy(elemtype, p.head);
             }
             result = new Attribute.Array(type, ats);
         }
         public void visitCompoundAnnotationProxy(CompoundAnnotationProxy proxy) {
             result = deproxyCompound(proxy);
         }
     }
     class AnnotationDefaultCompleter extends AnnotationDeproxy implements Annotate.Annotator {
         final MethodSymbol sym;
         final Attribute value;
         final JavaFileObject classFile = currentClassFile;
         @Override
         public String toString() {
             return " ClassReader store default for " + sym.owner + "." + sym + " is " + value;
         }
         AnnotationDefaultCompleter(MethodSymbol sym, Attribute value) {
             this.sym = sym;
             this.value = value;
         }
         // implement Annotate.Annotator.enterAnnotation()
         public void enterAnnotation() {
             JavaFileObject previousClassFile = currentClassFile;
             try {
                 // Reset the interim value set earlier in
                 // attachAnnotationDefault().
                 sym.defaultValue = null;
                 currentClassFile = classFile;
                 sym.defaultValue = deproxy(sym.type.getReturnType(), value);
             } finally {
                 currentClassFile = previousClassFile;
             }
         }
     }
     class AnnotationCompleter extends AnnotationDeproxy implements Annotate.Annotator {
         final Symbol sym;
         final List<CompoundAnnotationProxy> l;
         final JavaFileObject classFile;
         @Override
         public String toString() {
             return " ClassReader annotate " + sym.owner + "." + sym + " with " + l;
         }
         AnnotationCompleter(Symbol sym, List<CompoundAnnotationProxy> l) {
             this.sym = sym;
             this.l = l;
             this.classFile = currentClassFile;
         }
         // implement Annotate.Annotator.enterAnnotation()
         public void enterAnnotation() {
             JavaFileObject previousClassFile = currentClassFile;
             try {
                 currentClassFile = classFile;
                 Annotations annotations = sym.annotations;
                 List<Attribute.Compound> newList = deproxyCompoundList(l);
                 if (annotations.pendingCompletion()) {
                     annotations.setDeclarationAttributes(newList);
                 } else {
                     annotations.append(newList);
                 }
             } finally {
                 currentClassFile = previousClassFile;
             }
         }
     }
     class TypeAnnotationCompleter extends AnnotationCompleter {
         List<TypeAnnotationProxy> proxies;
         TypeAnnotationCompleter(Symbol sym,
                 List<TypeAnnotationProxy> proxies) {
             super(sym, List.<CompoundAnnotationProxy>nil());
             this.proxies = proxies;
         }
         List<Attribute.TypeCompound> deproxyTypeCompoundList(List<TypeAnnotationProxy> proxies) {
             ListBuffer<Attribute.TypeCompound> buf = ListBuffer.lb();
             for (TypeAnnotationProxy proxy: proxies) {
                 Attribute.Compound compound = deproxyCompound(proxy.compound);
                 Attribute.TypeCompound typeCompound = new Attribute.TypeCompound(compound, proxy.position);
                 buf.add(typeCompound);
             }
             return buf.toList();
         }
         @Override
         public void enterAnnotation() {
             JavaFileObject previousClassFile = currentClassFile;
             try {
                 currentClassFile = classFile;
                 List<Attribute.TypeCompound> newList = deproxyTypeCompoundList(proxies);
                 sym.annotations.setTypeAttributes(newList.prependList(sym.getRawTypeAttributes()));
             } finally {
                 currentClassFile = previousClassFile;
             }
         }
     }
 /************************************************************************
  * Reading Symbols
  ***********************************************************************/
     /** Read a field.
      */
     VarSymbol readField() {
         long flags = adjustFieldFlags(nextChar());
         Name name = readName(nextChar());
         Type type = readType(nextChar());
         VarSymbol v = new VarSymbol(flags, name, type, currentOwner);
         readMemberAttrs(v);
         return v;
     }
     /** Read a method.
      */
     MethodSymbol readMethod() {
         long flags = adjustMethodFlags(nextChar());
         Name name = readName(nextChar());
         Type type = readType(nextChar());
         if (currentOwner.isInterface() &&
                 (flags & ABSTRACT) == 0 && !name.equals(names.clinit)) {
             if (majorVersion > Target.JDK1_8.majorVersion ||
                     (majorVersion == Target.JDK1_8.majorVersion && minorVersion >= Target.JDK1_8.minorVersion)) {
                 currentOwner.flags_field |= DEFAULT;
                 flags |= DEFAULT | ABSTRACT;
             } else {
                 //protect against ill-formed classfiles
                 throw new CompletionFailure(currentOwner, "default method found in pre JDK 8 classfile");
             }
         }
         if (name == names.init && currentOwner.hasOuterInstance()) {
             // Sometimes anonymous classes don't have an outer
             // instance, however, there is no reliable way to tell so
             // we never strip this$n
             if (!currentOwner.name.isEmpty())
                 type = new MethodType(adjustMethodParams(flags, type.getParameterTypes()),
                                       type.getReturnType(),
                                       type.getThrownTypes(),
                                       syms.methodClass);
         }
         MethodSymbol m = new MethodSymbol(flags, name, type, currentOwner);
         if (saveParameterNames)
             initParameterNames(m);
         Symbol prevOwner = currentOwner;
         currentOwner = m;
         try {
             readMemberAttrs(m);
         } finally {
             currentOwner = prevOwner;
         }
         if (saveParameterNames)
             setParameterNames(m, type);
         return m;
     }
     private List<Type> adjustMethodParams(long flags, List<Type> args) {
         boolean isVarargs = (flags & VARARGS) != 0;
         if (isVarargs) {
             Type varargsElem = args.last();
             ListBuffer<Type> adjustedArgs = ListBuffer.lb();
             for (Type t : args) {
                 adjustedArgs.append(t != varargsElem ?
                     t :
                     ((ArrayType)t).makeVarargs());
             }
             args = adjustedArgs.toList();
         }
         return args.tail;
     }
     /**
      * Init the parameter names array.
      * Parameter names are currently inferred from the names in the
      * LocalVariableTable attributes of a Code attribute.
      * (Note: this means parameter names are currently not available for
      * methods without a Code attribute.)
      * This method initializes an array in which to store the name indexes
      * of parameter names found in LocalVariableTable attributes. It is
      * slightly supersized to allow for additional slots with a start_pc of 0.
      */
     void initParameterNames(MethodSymbol sym) {
         // make allowance for synthetic parameters.
         final int excessSlots = 4;
         int expectedParameterSlots =
                 Code.width(sym.type.getParameterTypes()) + excessSlots;
         if (parameterNameIndices == null
                 || parameterNameIndices.length < expectedParameterSlots) {
             parameterNameIndices = new int[expectedParameterSlots];
         } else
             Arrays.fill(parameterNameIndices, 0);
         haveParameterNameIndices = false;
         sawMethodParameters = false;
     }
     /**
      * Set the parameter names for a symbol from the name index in the
      * parameterNameIndicies array. The type of the symbol may have changed
      * while reading the method attributes (see the Signature attribute).
      * This may be because of generic information or because anonymous
      * synthetic parameters were added.   The original type (as read from
      * the method descriptor) is used to help guess the existence of
      * anonymous synthetic parameters.
      * On completion, sym.savedParameter names will either be null (if
      * no parameter names were found in the class file) or will be set to a
      * list of names, one per entry in sym.type.getParameterTypes, with
      * any missing names represented by the empty name.
      */
     void setParameterNames(MethodSymbol sym, Type jvmType) {
         // if no names were found in the class file, there's nothing more to do
         if (!haveParameterNameIndices)
             return;
         // If we get parameter names from MethodParameters, then we
         // don't need to skip.
         int firstParam = 0;
         if (!sawMethodParameters) {
             firstParam = ((sym.flags() & STATIC) == 0) ? 1 : 0;
             // the code in readMethod may have skipped the first
             // parameter when setting up the MethodType. If so, we
             // make a corresponding allowance here for the position of
             // the first parameter.  Note that this assumes the
             // skipped parameter has a width of 1 -- i.e. it is not
         // a double width type (long or double.)
         if (sym.name == names.init && currentOwner.hasOuterInstance()) {
             // Sometimes anonymous classes don't have an outer
             // instance, however, there is no reliable way to tell so
             // we never strip this$n
             if (!currentOwner.name.isEmpty())
                 firstParam += 1;
         }
         if (sym.type != jvmType) {
                 // reading the method attributes has caused the
                 // symbol's type to be changed. (i.e. the Signature
                 // attribute.)  This may happen if there are hidden
                 // (synthetic) parameters in the descriptor, but not
                 // in the Signature.  The position of these hidden
                 // parameters is unspecified; for now, assume they are
                 // at the beginning, and so skip over them. The
                 // primary case for this is two hidden parameters
                 // passed into Enum constructors.
             int skip = Code.width(jvmType.getParameterTypes())
                     - Code.width(sym.type.getParameterTypes());
             firstParam += skip;
         }
         }
         List<Name> paramNames = List.nil();
         int index = firstParam;
         for (Type t: sym.type.getParameterTypes()) {
             int nameIdx = (index < parameterNameIndices.length
                     ? parameterNameIndices[index] : 0);
             Name name = nameIdx == 0 ? names.empty : readName(nameIdx);
             paramNames = paramNames.prepend(name);
             index += Code.width(t);
         }
         sym.savedParameterNames = paramNames.reverse();
     }
     /**
      * skip n bytes
      */
     void skipBytes(int n) {
         bp = bp + n;
     }
     /** Skip a field or method
      */
     void skipMember() {
         bp = bp + 6;
         char ac = nextChar();
         for (int i = 0; i < ac; i++) {
             bp = bp + 2;
             int attrLen = nextInt();
             bp = bp + attrLen;
         }
     }
     /** Enter type variables of this classtype and all enclosing ones in
      *  `typevars'.
      */
     protected void enterTypevars(Type t) {
         if (t.getEnclosingType() != null && t.getEnclosingType().hasTag(CLASS))
             enterTypevars(t.getEnclosingType());
         for (List<Type> xs = t.getTypeArguments(); xs.nonEmpty(); xs = xs.tail)
             typevars.enter(xs.head.tsym);
     }
     protected void enterTypevars(Symbol sym) {
         if (sym.owner.kind == MTH) {
             enterTypevars(sym.owner);
             enterTypevars(sym.owner.owner);
         }
         enterTypevars(sym.type);
     }
     /** Read contents of a given class symbol `c'. Both external and internal
      *  versions of an inner class are read.
      */
     void readClass(ClassSymbol c) {
         ClassType ct = (ClassType)c.type;
         // allocate scope for members
         c.members_field = new Scope(c);
         // prepare type variable table
         typevars = typevars.dup(currentOwner);
         if (ct.getEnclosingType().hasTag(CLASS))
             enterTypevars(ct.getEnclosingType());
         // read flags, or skip if this is an inner class
         long flags = adjustClassFlags(nextChar());
         if (c.owner.kind == PCK) c.flags_field = flags;
         // read own class name and check that it matches
         ClassSymbol self = readClassSymbol(nextChar());
         if (c != self)
             throw badClassFile("class.file.wrong.class",
                                self.flatname);
         // class attributes must be read before class
         // skip ahead to read class attributes
         int startbp = bp;
         nextChar();
         char interfaceCount = nextChar();
         bp += interfaceCount * 2;
         char fieldCount = nextChar();
         for (int i = 0; i < fieldCount; i++) skipMember();
         char methodCount = nextChar();
         for (int i = 0; i < methodCount; i++) skipMember();
         readClassAttrs(c);
         if (readAllOfClassFile) {
             for (int i = 1; i < poolObj.length; i++) readPool(i);
             c.pool = new Pool(poolObj.length, poolObj, types);
         }
         // reset and read rest of classinfo
         bp = startbp;
         int n = nextChar();
         if (ct.supertype_field == null)
             ct.supertype_field = (n == 0)
                 ? Type.noType
                 : readClassSymbol(n).erasure(types);
         n = nextChar();
         List<Type> is = List.nil();
         for (int i = 0; i < n; i++) {
             Type _inter = readClassSymbol(nextChar()).erasure(types);
             is = is.prepend(_inter);
         }
         if (ct.interfaces_field == null)
             ct.interfaces_field = is.reverse();
         Assert.check(fieldCount == nextChar());
         for (int i = 0; i < fieldCount; i++) enterMember(c, readField());
         Assert.check(methodCount == nextChar());
         for (int i = 0; i < methodCount; i++) enterMember(c, readMethod());
         typevars = typevars.leave();
     }
     /** Read inner class info. For each inner/outer pair allocate a
      *  member class.
      */
     void readInnerClasses(ClassSymbol c) {
         int n = nextChar();
         for (int i = 0; i < n; i++) {
             nextChar(); // skip inner class symbol
             ClassSymbol outer = readClassSymbol(nextChar());
             Name name = readName(nextChar());
             if (name == null) name = names.empty;
             long flags = adjustClassFlags(nextChar());
             if (outer != null) { // we have a member class
                 if (name == names.empty)
                     name = names.one;
                 ClassSymbol member = enterClass(name, outer);
                 if ((flags & STATIC) == 0) {
                     ((ClassType)member.type).setEnclosingType(outer.type);
                     if (member.erasure_field != null)
                         ((ClassType)member.erasure_field).setEnclosingType(types.erasure(outer.type));
                 }
                 if (c == outer) {
                     member.flags_field = flags;
                     enterMember(c, member);
                 }
             }
         }
     }
     /** Read a class file.
      */
     private void readClassFile(ClassSymbol c) throws IOException {
         int magic = nextInt();
         if (magic != JAVA_MAGIC)
             throw badClassFile("illegal.start.of.class.file");
         minorVersion = nextChar();
         majorVersion = nextChar();
         int maxMajor = Target.MAX().majorVersion;
         int maxMinor = Target.MAX().minorVersion;
         if (majorVersion > maxMajor ||
             majorVersion * 1000 + minorVersion <
             Target.MIN().majorVersion * 1000 + Target.MIN().minorVersion)
         {
             if (majorVersion == (maxMajor + 1))
                 log.warning("big.major.version",
                             currentClassFile,
                             majorVersion,
                             maxMajor);
             else
                 throw badClassFile("wrong.version",
                                    Integer.toString(majorVersion),
                                    Integer.toString(minorVersion),
                                    Integer.toString(maxMajor),
                                    Integer.toString(maxMinor));
         }
         else if (checkClassFile &&
                  majorVersion == maxMajor &&
                  minorVersion > maxMinor)
         {
             printCCF("found.later.version",
                      Integer.toString(minorVersion));
         }
         indexPool();
         if (signatureBuffer.length < bp) {
             int ns = Integer.highestOneBit(bp) << 1;
             signatureBuffer = new byte[ns];
         }
         readClass(c);
     }
 /************************************************************************
  * Adjusting flags
  ***********************************************************************/
     long adjustFieldFlags(long flags) {
         return flags;
     }
     long adjustMethodFlags(long flags) {
         if ((flags & ACC_BRIDGE) != 0) {
             flags &= ~ACC_BRIDGE;
             flags |= BRIDGE;
             if (!allowGenerics)
                 flags &= ~SYNTHETIC;
         }
         if ((flags & ACC_VARARGS) != 0) {
             flags &= ~ACC_VARARGS;
             flags |= VARARGS;
         }
         return flags;
     }
     long adjustClassFlags(long flags) {
         return flags & ~ACC_SUPER; // SUPER and SYNCHRONIZED bits overloaded
     }
 /************************************************************************
  * Loading Classes
  ***********************************************************************/
     /** Define a new class given its name and owner.
      */
     public ClassSymbol defineClass(Name name, Symbol owner) {
         ClassSymbol c = new ClassSymbol(0, name, owner);
         if (owner.kind == PCK)
             Assert.checkNull(classes.get(c.flatname), c);
         c.completer = this;
         return c;
     }
     /** Create a new toplevel or member class symbol with given name
      *  and owner and enter in `classes' unless already there.
      */
     public ClassSymbol enterClass(Name name, TypeSymbol owner) {
         Name flatname = TypeSymbol.formFlatName(name, owner);
         ClassSymbol c = classes.get(flatname);
         if (c == null) {
             c = defineClass(name, owner);
             classes.put(flatname, c);
         } else if ((c.name != name || c.owner != owner) && owner.kind == TYP && c.owner.kind == PCK) {
             // reassign fields of classes that might have been loaded with
             // their flat names.
             c.owner.members().remove(c);
             c.name = name;
             c.owner = owner;
             c.fullname = ClassSymbol.formFullName(name, owner);
         }
         return c;
     }
     /**
      * Creates a new toplevel class symbol with given flat name and
      * given class (or source) file.
      *
      * @param flatName a fully qualified binary class name
      * @param classFile the class file or compilation unit defining
      * the class (may be {@code null})
      * @return a newly created class symbol
      * @throws AssertionError if the class symbol already exists
      */
     public ClassSymbol enterClass(Name flatName, JavaFileObject classFile) {
         ClassSymbol cs = classes.get(flatName);
         if (cs != null) {
             String msg = Log.format("%s: completer = %s; class file = %s; source file = %s",
                                     cs.fullname,
                                     cs.completer,
                                     cs.classfile,
                                     cs.sourcefile);
             throw new AssertionError(msg);
         }
         Name packageName = Convert.packagePart(flatName);
         PackageSymbol owner = packageName.isEmpty()
                                 ? syms.unnamedPackage
                                 : enterPackage(packageName);
         cs = defineClass(Convert.shortName(flatName), owner);
         cs.classfile = classFile;
         classes.put(flatName, cs);
         return cs;
     }
     /** Create a new member or toplevel class symbol with given flat name
      *  and enter in `classes' unless already there.
      */
     public ClassSymbol enterClass(Name flatname) {
         ClassSymbol c = classes.get(flatname);
         if (c == null)
             return enterClass(flatname, (JavaFileObject)null);
         else
             return c;
     }
     private boolean suppressFlush = false;
     /** Completion for classes to be loaded. Before a class is loaded
      *  we make sure its enclosing class (if any) is loaded.
      */
     public void complete(Symbol sym) throws CompletionFailure {
         if (sym.kind == TYP) {
             ClassSymbol c = (ClassSymbol)sym;
             c.members_field = new Scope.ErrorScope(c); // make sure it's always defined
             boolean saveSuppressFlush = suppressFlush;
             suppressFlush = true;
             try {
                 completeOwners(c.owner);
                 completeEnclosing(c);
             } finally {
                 suppressFlush = saveSuppressFlush;
             }
             fillIn(c);
         } else if (sym.kind == PCK) {
             PackageSymbol p = (PackageSymbol)sym;
             try {
                 fillIn(p);
             } catch (IOException ex) {
                 throw new CompletionFailure(sym, ex.getLocalizedMessage()).initCause(ex);
             }
         }
         if (!filling && !suppressFlush)
             annotate.flush(); // finish attaching annotations
     }
     /** complete up through the enclosing package. */
     private void completeOwners(Symbol o) {
         if (o.kind != PCK) completeOwners(o.owner);
         o.complete();
     }
     /**
      * Tries to complete lexically enclosing classes if c looks like a
      * nested class.  This is similar to completeOwners but handles
      * the situation when a nested class is accessed directly as it is
      * possible with the Tree API or javax.lang.model.*.
      */
     private void completeEnclosing(ClassSymbol c) {
         if (c.owner.kind == PCK) {
             Symbol owner = c.owner;
             for (Name name : Convert.enclosingCandidates(Convert.shortName(c.name))) {
                 Symbol encl = owner.members().lookup(name).sym;
                 if (encl == null)
                     encl = classes.get(TypeSymbol.formFlatName(name, owner));
                 if (encl != null)
                     encl.complete();
             }
         }
     }
     /** We can only read a single class file at a time; this
      *  flag keeps track of when we are currently reading a class
      *  file.
      */
     private boolean filling = false;
     /** Fill in definition of class `c' from corresponding class or
      *  source file.
      */
     private void fillIn(ClassSymbol c) {
         if (completionFailureName == c.fullname) {
             throw new CompletionFailure(c, "user-selected completion failure by class name");
         }
         currentOwner = c;
         warnedAttrs.clear();
         JavaFileObject classfile = c.classfile;
         if (classfile != null) {
             JavaFileObject previousClassFile = currentClassFile;
             try {
                 if (filling) {
                     Assert.error("Filling " + classfile.toUri() + " during " + previousClassFile);
                 }
                 currentClassFile = classfile;
                 if (verbose) {
                     log.printVerbose("loading", currentClassFile.toString());
                 }
                 if (classfile.getKind() == JavaFileObject.Kind.CLASS) {
                     filling = true;
                     try {
                         bp = 0;
                         buf = readInputStream(buf, classfile.openInputStream());
                         readClassFile(c);
                         if (!missingTypeVariables.isEmpty() && !foundTypeVariables.isEmpty()) {
                             List<Type> missing = missingTypeVariables;
                             List<Type> found = foundTypeVariables;
                             missingTypeVariables = List.nil();
                             foundTypeVariables = List.nil();
                             filling = false;
                             ClassType ct = (ClassType)currentOwner.type;
                             ct.supertype_field =
                                 types.subst(ct.supertype_field, missing, found);
                             ct.interfaces_field =
                                 types.subst(ct.interfaces_field, missing, found);
                         } else if (missingTypeVariables.isEmpty() !=
                                    foundTypeVariables.isEmpty()) {
                             Name name = missingTypeVariables.head.tsym.name;
                             throw badClassFile("undecl.type.var", name);
                         }
                     } finally {
                         missingTypeVariables = List.nil();
                         foundTypeVariables = List.nil();
                         filling = false;
                     }
                 } else {
                     if (sourceCompleter != null) {
                         sourceCompleter.complete(c);
                     } else {
                         throw new IllegalStateException("Source completer required to read "
                                                         + classfile.toUri());
                     }
                 }
                 return;
             } catch (IOException ex) {
                 throw badClassFile("unable.to.access.file", ex.getMessage());
             } finally {
                 currentClassFile = previousClassFile;
             }
         } else {
             JCDiagnostic diag =
                 diagFactory.fragment("class.file.not.found", c.flatname);
             throw
                 newCompletionFailure(c, diag);
         }
     }
     // where
         private static byte[] readInputStream(byte[] buf, InputStream s) throws IOException {
             try {
                 buf = ensureCapacity(buf, s.available());
                 int r = s.read(buf);
                 int bp = 0;
                 while (r != -1) {
                     bp += r;
                     buf = ensureCapacity(buf, bp);
                     r = s.read(buf, bp, buf.length - bp);
                 }
                 return buf;
             } finally {
                 try {
                     s.close();
                 } catch (IOException e) {
                     /* Ignore any errors, as this stream may have already
                      * thrown a related exception which is the one that
                      * should be reported.
                      */
                 }
             }
         }
         /*
          * ensureCapacity will increase the buffer as needed, taking note that
          * the new buffer will always be greater than the needed and never
          * exactly equal to the needed size or bp. If equal then the read (above)
          * will infinitely loop as buf.length - bp == 0.
          */
         private static byte[] ensureCapacity(byte[] buf, int needed) {
             if (buf.length <= needed) {
                 byte[] old = buf;
                 buf = new byte[Integer.highestOneBit(needed) << 1];
                 System.arraycopy(old, 0, buf, 0, old.length);
             }
             return buf;
         }
         /** Static factory for CompletionFailure objects.
          *  In practice, only one can be used at a time, so we share one
          *  to reduce the expense of allocating new exception objects.
          */
         private CompletionFailure newCompletionFailure(TypeSymbol c,
                                                        JCDiagnostic diag) {
             if (!cacheCompletionFailure) {
                 // log.warning("proc.messager",
                 //             Log.getLocalizedString("class.file.not.found", c.flatname));
                 // c.debug.printStackTrace();
                 return new CompletionFailure(c, diag);
             } else {
                 CompletionFailure result = cachedCompletionFailure;
                 result.sym = c;
                 result.diag = diag;
                 return result;
             }
         }
         private CompletionFailure cachedCompletionFailure =
             new CompletionFailure(null, (JCDiagnostic) null);
         {
             cachedCompletionFailure.setStackTrace(new StackTraceElement[0]);
         }
     /** Load a toplevel class with given fully qualified name
      *  The class is entered into `classes' only if load was successful.
      */
     public ClassSymbol loadClass(Name flatname) throws CompletionFailure {
         boolean absent = classes.get(flatname) == null;
         ClassSymbol c = enterClass(flatname);
         if (c.members_field == null && c.completer != null) {
             try {
                 c.complete();
             } catch (CompletionFailure ex) {
                 if (absent) classes.remove(flatname);
                 throw ex;
             }
         }
         return c;
     }
 /************************************************************************
  * Loading Packages
  ***********************************************************************/
     /** Check to see if a package exists, given its fully qualified name.
      */
     public boolean packageExists(Name fullname) {
         return enterPackage(fullname).exists();
     }
     /** Make a package, given its fully qualified name.
      */
     public PackageSymbol enterPackage(Name fullname) {
         PackageSymbol p = packages.get(fullname);
         if (p == null) {
             Assert.check(!fullname.isEmpty(), "rootPackage missing!");
             p = new PackageSymbol(
                 Convert.shortName(fullname),
                 enterPackage(Convert.packagePart(fullname)));
             p.completer = this;
             packages.put(fullname, p);
         }
         return p;
     }
     /** Make a package, given its unqualified name and enclosing package.
      */
     public PackageSymbol enterPackage(Name name, PackageSymbol owner) {
         return enterPackage(TypeSymbol.formFullName(name, owner));
     }
     /** Include class corresponding to given class file in package,
      *  unless (1) we already have one the same kind (.class or .java), or
      *         (2) we have one of the other kind, and the given class file
      *             is older.
      */
     protected void includeClassFile(PackageSymbol p, JavaFileObject file) {
         if ((p.flags_field & EXISTS) == 0)
             for (Symbol q = p; q != null && q.kind == PCK; q = q.owner)
                 q.flags_field |= EXISTS;
         JavaFileObject.Kind kind = file.getKind();
         int seen;
         if (kind == JavaFileObject.Kind.CLASS)
             seen = CLASS_SEEN;
         else
             seen = SOURCE_SEEN;
         String binaryName = fileManager.inferBinaryName(currentLoc, file);
         int lastDot = binaryName.lastIndexOf(".");
         Name classname = names.fromString(binaryName.substring(lastDot + 1));
         boolean isPkgInfo = classname == names.package_info;
         ClassSymbol c = isPkgInfo
             ? p.package_info
             : (ClassSymbol) p.members_field.lookup(classname).sym;
         if (c == null) {
             c = enterClass(classname, p);
             if (c.classfile == null) // only update the file if's it's newly created
                 c.classfile = file;
             if (isPkgInfo) {
                 p.package_info = c;
             } else {
                 if (c.owner == p)  // it might be an inner class
                     p.members_field.enter(c);
             }
         } else if (c.classfile != null && (c.flags_field & seen) == 0) {
             // if c.classfile == null, we are currently compiling this class
             // and no further action is necessary.
             // if (c.flags_field & seen) != 0, we have already encountered
             // a file of the same kind; again no further action is necessary.
             if ((c.flags_field & (CLASS_SEEN | SOURCE_SEEN)) != 0)
                 c.classfile = preferredFileObject(file, c.classfile);
         }
         c.flags_field |= seen;
     }
     /** Implement policy to choose to derive information from a source
      *  file or a class file when both are present.  May be overridden
      *  by subclasses.
      */
     protected JavaFileObject preferredFileObject(JavaFileObject a,
                                            JavaFileObject b) {
         if (preferSource)
             return (a.getKind() == JavaFileObject.Kind.SOURCE) ? a : b;
         else {
             long adate = a.getLastModified();
             long bdate = b.getLastModified();
             // 6449326: policy for bad lastModifiedTime in ClassReader
             //assert adate >= 0 && bdate >= 0;
             return (adate > bdate) ? a : b;
         }
     }
     /**
      * specifies types of files to be read when filling in a package symbol
      */
     protected EnumSet<JavaFileObject.Kind> getPackageFileKinds() {
         return EnumSet.of(JavaFileObject.Kind.CLASS, JavaFileObject.Kind.SOURCE);
     }
     /**
      * this is used to support javadoc
      */
     protected void extraFileActions(PackageSymbol pack, JavaFileObject fe) {
     }
     protected Location currentLoc; // FIXME
     private boolean verbosePath = true;
     /** Load directory of package into members scope.
      */
     private void fillIn(PackageSymbol p) throws IOException {
         if (p.members_field == null) p.members_field = new Scope(p);
         String packageName = p.fullname.toString();
         Set<JavaFileObject.Kind> kinds = getPackageFileKinds();
         fillIn(p, PLATFORM_CLASS_PATH,
                fileManager.list(PLATFORM_CLASS_PATH,
                                 packageName,
                                 EnumSet.of(JavaFileObject.Kind.CLASS),
                                 false));
         Set<JavaFileObject.Kind> classKinds = EnumSet.copyOf(kinds);
         classKinds.remove(JavaFileObject.Kind.SOURCE);
         boolean wantClassFiles = !classKinds.isEmpty();
         Set<JavaFileObject.Kind> sourceKinds = EnumSet.copyOf(kinds);
         sourceKinds.remove(JavaFileObject.Kind.CLASS);
         boolean wantSourceFiles = !sourceKinds.isEmpty();
         boolean haveSourcePath = fileManager.hasLocation(SOURCE_PATH);
         if (verbose && verbosePath) {
             if (fileManager instanceof StandardJavaFileManager) {
                 StandardJavaFileManager fm = (StandardJavaFileManager)fileManager;
                 if (haveSourcePath && wantSourceFiles) {
                     List<File> path = List.nil();
                     for (File file : fm.getLocation(SOURCE_PATH)) {
                         path = path.prepend(file);
                     }
                     log.printVerbose("sourcepath", path.reverse().toString());
                 } else if (wantSourceFiles) {
                     List<File> path = List.nil();
                     for (File file : fm.getLocation(CLASS_PATH)) {
                         path = path.prepend(file);
                     }
                     log.printVerbose("sourcepath", path.reverse().toString());
                 }
                 if (wantClassFiles) {
                     List<File> path = List.nil();
                     for (File file : fm.getLocation(PLATFORM_CLASS_PATH)) {
                         path = path.prepend(file);
                     }
                     for (File file : fm.getLocation(CLASS_PATH)) {
                         path = path.prepend(file);
                     }
                     log.printVerbose("classpath",  path.reverse().toString());
                 }
             }
         }
         if (wantSourceFiles && !haveSourcePath) {
             fillIn(p, CLASS_PATH,
                    fileManager.list(CLASS_PATH,
                                     packageName,
                                     kinds,
                                     false));
         } else {
             if (wantClassFiles)
                 fillIn(p, CLASS_PATH,
                        fileManager.list(CLASS_PATH,
                                         packageName,
                                         classKinds,
                                         false));
             if (wantSourceFiles)
                 fillIn(p, SOURCE_PATH,
                        fileManager.list(SOURCE_PATH,
                                         packageName,
                                         sourceKinds,
                                         false));
         }
         verbosePath = false;
     }
     // where
         private void fillIn(PackageSymbol p,
                             Location location,
                             Iterable<JavaFileObject> files)
         {
             currentLoc = location;
             for (JavaFileObject fo : files) {
                 switch (fo.getKind()) {
                 case CLASS:
                 case SOURCE: {
                     // TODO pass binaryName to includeClassFile
                     String binaryName = fileManager.inferBinaryName(currentLoc, fo);
                     String simpleName = binaryName.substring(binaryName.lastIndexOf(".") + 1);
                     if (SourceVersion.isIdentifier(simpleName) ||
                         simpleName.equals("package-info"))
                         includeClassFile(p, fo);
                     break;
                 }
                 default:
                     extraFileActions(p, fo);
                 }
             }
         }
     /** Output for "-checkclassfile" option.
      *  @param key The key to look up the correct internationalized string.
      *  @param arg An argument for substitution into the output string.
      */
     private void printCCF(String key, Object arg) {
         log.printLines(key, arg);
     }
     public interface SourceCompleter {
         void complete(ClassSymbol sym)
             throws CompletionFailure;
     }
     /**
      * A subclass of JavaFileObject for the sourcefile attribute found in a classfile.
      * The attribute is only the last component of the original filename, so is unlikely
      * to be valid as is, so operations other than those to access the name throw
      * UnsupportedOperationException
      */
     private static class SourceFileObject extends BaseFileObject {
         /** The file's name.
          */
         private Name name;
         private Name flatname;
         public SourceFileObject(Name name, Name flatname) {
             super(null); // no file manager; never referenced for this file object
             this.name = name;
             this.flatname = flatname;
         }
         @Override
         public URI toUri() {
             try {
                 return new URI(null, name.toString(), null);
             } catch (URISyntaxException e) {
                 throw new CannotCreateUriError(name.toString(), e);
             }
         }
         @Override
         public String getName() {
             return name.toString();
         }
         @Override
         public String getShortName() {
             return getName();
         }
         @Override
         public JavaFileObject.Kind getKind() {
             return getKind(getName());
         }
         @Override
         public InputStream openInputStream() {
             throw new UnsupportedOperationException();
         }
         @Override
         public OutputStream openOutputStream() {
             throw new UnsupportedOperationException();
         }
         @Override
         public CharBuffer getCharContent(boolean ignoreEncodingErrors) {
             throw new UnsupportedOperationException();
         }
         @Override
         public Reader openReader(boolean ignoreEncodingErrors) {
             throw new UnsupportedOperationException();
         }
         @Override
         public Writer openWriter() {
             throw new UnsupportedOperationException();
         }
         @Override
         public long getLastModified() {
             throw new UnsupportedOperationException();
         }
         @Override
         public boolean delete() {
             throw new UnsupportedOperationException();
         }
         @Override
         protected String inferBinaryName(Iterable<? extends File> path) {
             return flatname.toString();
         }
         @Override
         public boolean isNameCompatible(String simpleName, JavaFileObject.Kind kind) {
             return true; // fail-safe mode
         }
         /**
          * Check if two file objects are equal.
          * SourceFileObjects are just placeholder objects for the value of a
          * SourceFile attribute, and do not directly represent specific files.
          * Two SourceFileObjects are equal if their names are equal.
          */
         @Override
         public boolean equals(Object other) {
             if (this == other)
                 return true;
             if (!(other instanceof SourceFileObject))
                 return false;
             SourceFileObject o = (SourceFileObject) other;
             return name.equals(o.name);
         }
         @Override
         public int hashCode() {
             return name.hashCode();
         }
     }
 }

Mercurial > jdk8-mips64-public > langtools / annotate

src/share/classes/com/sun/tools/javac/jvm/ClassReader.java@71f35e4b93a5 (annotated)

src/share/classes/com/sun/tools/javac/jvm/ClassReader.java