Mercurial > jdk8-mips64-public > langtools / file revision

 /*

  * Copyright 1999-2006 Sun Microsystems, Inc.  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.  Sun designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.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.nio.CharBuffer;

 import java.util.EnumSet;

 import java.util.HashMap;

 import java.util.Map;

 import java.util.Set;

 import javax.lang.model.SourceVersion;

 import javax.tools.JavaFileObject;

 import javax.tools.JavaFileManager;

 import javax.tools.StandardJavaFileManager;

 import com.sun.tools.javac.comp.Annotate;

 import com.sun.tools.javac.code.*;

 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.List;

 import static com.sun.tools.javac.code.Flags.*;

 import static com.sun.tools.javac.code.Kinds.*;

 import static com.sun.tools.javac.code.TypeTags.*;

 import com.sun.tools.javac.jvm.ClassFile.NameAndType;

 import javax.tools.JavaFileManager.Location;

 import static javax.tools.StandardLocation.*;

 /** 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 API supported by Sun Microsystems.  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 extends ClassFile implements Completer {

     /** The context key for the class reader. */

     protected static final Context.Key<ClassReader> classReaderKey =

         new Context.Key<ClassReader>();

     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: 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 Name.Table 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[0x0fff0];

     /** The current input pointer.

      */

     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;

     /** 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 packages == null || packages == syms.packages;

             packages = syms.packages;

             assert 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 = Name.Table.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.get("-verbose")        != null;

         checkClassFile = options.get("-checkclassfile") != null;

         Source source = Source.instance(context);

         allowGenerics    = source.allowGenerics();

         allowVarargs     = source.allowVarargs();

         allowAnnotations = source.allowAnnotations();

         saveParameterNames = options.get("save-parameter-names") != null;

         cacheCompletionFailure = options.get("dev") == null;

         preferSource = "source".equals(options.get("-Xprefer"));

         completionFailureName =

             (options.get("failcomplete") != null)

             ? names.fromString(options.get("failcomplete"))

             : null;

         typevars = new Scope(syms.noSymbol);

     }

     /** 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 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:

                 bp = bp + 2;

                 break;

             case CONSTANT_Fieldref:

             case CONSTANT_Methodref:

             case CONSTANT_InterfaceMethodref:

             case CONSTANT_NameandType:

             case CONSTANT_Integer:

             case CONSTANT_Float:

                 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.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.type, owner);

             break;

         }

         case CONSTANT_NameandType:

             poolObj[i] = new NameAndType(

                 readName(getChar(index + 1)),

                 readType(getChar(index + 3)));

             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;

         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 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 name.

      */

     Type sigToType(Name sig) {

         return sig == null

             ? null

             : sigToType(sig.table.names, sig.index, sig.len);

     }

     /** 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;

                         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();

                         }

                         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"

                             3;  // ".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 name.

      */

     List<Type> sigToTypeParams(Name name) {

         return sigToTypeParams(name.table.names, name.index, name.len);

     }

     /** 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();

         Type st = null;

         if (signature[sigp] == ':' && signature[sigp+1] == ':') {

             sigp++;

             st = syms.objectType;

         }

         while (signature[sigp] == ':') {

             sigp++;

             bounds = bounds.prepend(sigToType());

         }

         if (!sigEnterPhase) {

             types.setBounds(tvar, bounds.reverse(), st);

         }

         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

  ***********************************************************************/

     /** Report unrecognized attribute.

      */

     void unrecognized(Name attrName) {

         if (checkClassFile)

             printCCF("ccf.unrecognized.attribute", attrName);

     }

     /** Read member attribute.

      */

     void readMemberAttr(Symbol sym, Name attrName, int attrLen) {

         //- System.err.println(" z " + sym + ", " + attrName + ", " + attrLen);

         if (attrName == names.ConstantValue) {

             Object v = readPool(nextChar());

             // Ignore ConstantValue attribute if field not final.

             if ((sym.flags() & FINAL) != 0)

                 ((VarSymbol)sym).setData(v);

         } else if (attrName == names.Code) {

             if (readAllOfClassFile || saveParameterNames)

                 ((MethodSymbol)sym).code = readCode(sym);

             else

                 bp = bp + attrLen;

         } else if (attrName == names.Exceptions) {

             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();

         } else if (attrName == names.Synthetic) {

             // bridge methods are visible when generics not enabled

             if (allowGenerics || (sym.flags_field & BRIDGE) == 0)

                 sym.flags_field |= SYNTHETIC;

         } else if (attrName == names.Bridge) {

             sym.flags_field |= BRIDGE;

             if (!allowGenerics)

                 sym.flags_field &= ~SYNTHETIC;

         } else if (attrName == names.Deprecated) {

             sym.flags_field |= DEPRECATED;

         } else if (attrName == names.Varargs) {

             if (allowVarargs) sym.flags_field |= VARARGS;

         } else if (attrName == names.Annotation) {

             if (allowAnnotations) sym.flags_field |= ANNOTATION;

         } else if (attrName == names.Enum) {

             sym.flags_field |= ENUM;

         } else if (allowGenerics && attrName == names.Signature) {

             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;

         } else if (attrName == names.RuntimeVisibleAnnotations) {

             attachAnnotations(sym);

         } else if (attrName == names.RuntimeInvisibleAnnotations) {

             attachAnnotations(sym);

         } else if (attrName == names.RuntimeVisibleParameterAnnotations) {

             attachParameterAnnotations(sym);

         } else if (attrName == names.RuntimeInvisibleParameterAnnotations) {

             attachParameterAnnotations(sym);

         } else if (attrName == names.LocalVariableTable) {

             int newbp = bp + attrLen;

             if (saveParameterNames) {

                 // pick up parameter names from the variable table

                 List<Name> parameterNames = List.nil();

                 int firstParam = ((sym.flags() & STATIC) == 0) ? 1 : 0;

                 int endParam = firstParam + Code.width(sym.type.getParameterTypes());

                 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 &&

                         firstParam <= register &&

                         register < endParam) {

                         int index = firstParam;

                         for (Type t : sym.type.getParameterTypes()) {

                             if (index == register) {

                                 parameterNames = parameterNames.prepend(readName(nameIndex));

                                 break;

                             }

                             index += Code.width(t);

                         }

                     }

                 }

                 parameterNames = parameterNames.reverse();

                 ((MethodSymbol)sym).savedParameterNames = parameterNames;

             }

             bp = newbp;

         } else if (attrName == names.AnnotationDefault) {

             attachAnnotationDefault(sym);

         } else if (attrName == names.EnclosingMethod) {

             int newbp = bp + attrLen;

             readEnclosingMethodAttr(sym);

             bp = newbp;

         } else {

             unrecognized(attrName);

             bp = bp + attrLen;

         }

     }

     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());

         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.len == 0)

             self.fullname = null;

         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.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.type.getParameterTypes().isEmpty())

             // no parameters

             return null;

         // A constructor of an inner class.

         // Remove the first argument (the enclosing instance)

         nt.type = new MethodType(nt.type.getParameterTypes().tail,

                                  nt.type.getReturnType(),

                                  nt.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) {

         char ac = nextChar();

         for (int i = 0; i < ac; i++) {

             Name attrName = readName(nextChar());

             int attrLen = nextInt();

             readMemberAttr(sym, attrName, attrLen);

         }

     }

     /** Read class attribute.

      */

     void readClassAttr(ClassSymbol c, Name attrName, int attrLen) {

         if (attrName == names.SourceFile) {

             Name n = readName(nextChar());

             c.sourcefile = new SourceFileObject(n);

         } else if (attrName == names.InnerClasses) {

             readInnerClasses(c);

         } else if (allowGenerics && attrName == names.Signature) {

             readingClassAttr = true;

             try {

                 ClassType ct1 = (ClassType)c.type;

                 assert 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 {

             readMemberAttr(c, attrName, attrLen);

         }

     }

     private boolean readingClassAttr = false;

     private List<Type> missingTypeVariables = List.nil();

     private List<Type> foundTypeVariables = List.nil();

     /** Read class attributes.

      */

     void readClassAttrs(ClassSymbol c) {

         char ac = nextChar();

         for (int i = 0; i < ac; i++) {

             Name attrName = readName(nextChar());

             int attrLen = nextInt();

             readClassAttr(c, attrName, attrLen);

         }

     }

     /** 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.later(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);

         }

     }

     /** 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();

         annotate.later(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());

     }

     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); }

         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); }

         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); }

         public String toString() {

             StringBuffer buf = new StringBuffer();

             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();

         }

     }

     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.getMessage());

                 }

             } 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;

             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;

                 }

             }

             if (enumerator == null) {

                 log.error("unknown.enum.constant",

                           currentClassFile, enumTypeSym, proxy.enumerator);

                 result = new Attribute.Error(enumTypeSym.type);

             } 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;

         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 {

                 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;

         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;

                 List<Attribute.Compound> newList = deproxyCompoundList(l);

                 sym.attributes_field = ((sym.attributes_field == null)

                                         ? newList

                                         : newList.prependList(sym.attributes_field));

             } 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 (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.len != 0)

                 type = new MethodType(type.getParameterTypes().tail,

                                       type.getReturnType(),

                                       type.getThrownTypes(),

                                       syms.methodClass);

         }

         MethodSymbol m = new MethodSymbol(flags, name, type, currentOwner);

         Symbol prevOwner = currentOwner;

         currentOwner = m;

         try {

             readMemberAttrs(m);

         } finally {

             currentOwner = prevOwner;

         }

         return m;

     }

     /** 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().tag == 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().tag == 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);

         }

         // 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();

         if (fieldCount != nextChar()) assert false;

         for (int i = 0; i < fieldCount; i++) enterMember(c, readField());

         if (methodCount != nextChar()) assert false;

         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");

         int minorVersion = nextChar();

         int 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 classes.get(c.flatname) == null : 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 suppressFlush = this.suppressFlush;

             this.suppressFlush = true;

             try {

                 completeOwners(c.owner);

                 completeEnclosing(c);

             } finally {

                 this.suppressFlush = suppressFlush;

             }

             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;

         JavaFileObject classfile = c.classfile;

         if (classfile != null) {

             JavaFileObject previousClassFile = currentClassFile;

             try {

                 assert !filling :

                     "Filling " + classfile.toUri() +

                     " during " + previousClassFile;

                 currentClassFile = classfile;

                 if (verbose) {

                     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.

                      */

                 }

             }

         }

         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 !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);

                     }

                     printVerbose("sourcepath", path.reverse().toString());

                 } else if (wantSourceFiles) {

                     List<File> path = List.nil();

                     for (File file : fm.getLocation(CLASS_PATH)) {

                         path = path.prepend(file);

                     }

                     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);

                     }

                     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 "-verbose" option.

      *  @param key The key to look up the correct internationalized string.

      *  @param arg An argument for substitution into the output string.

      */

     private void printVerbose(String key, CharSequence arg) {

         Log.printLines(log.noticeWriter, Log.getLocalizedString("verbose." + key, arg));

     }

     /** 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(log.noticeWriter, Log.getLocalizedString(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;

         public SourceFileObject(Name name) {

             this.name = name;

         }

         public InputStream openInputStream() {

             throw new UnsupportedOperationException();

         }

         public OutputStream openOutputStream() {

             throw new UnsupportedOperationException();

         }

         public Reader openReader() {

             throw new UnsupportedOperationException();

         }

         public Writer openWriter() {

             throw new UnsupportedOperationException();

         }

         /** @deprecated see bug 6410637 */

         @Deprecated

         public String getName() {

             return name.toString();

         }

         public long getLastModified() {

             throw new UnsupportedOperationException();

         }

         public boolean delete() {

             throw new UnsupportedOperationException();

         }

         public CharBuffer getCharContent(boolean ignoreEncodingErrors) {

             throw new UnsupportedOperationException();

         }

         @Override

         public boolean equals(Object other) {

             if (!(other instanceof SourceFileObject))

                 return false;

             SourceFileObject o = (SourceFileObject) other;

             return name.equals(o.name);

         }

         @Override

         public int hashCode() {

             return name.hashCode();

         }

         public boolean isNameCompatible(String simpleName, JavaFileObject.Kind kind) {

             return true; // fail-safe mode

         }

         public URI toUri() {

             return URI.create(name.toString());

         }

         public Reader openReader(boolean ignoreEncodingErrors) throws IOException {

             throw new UnsupportedOperationException();

         }

     }

 }