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

 /*

  * Copyright (c) 1999, 2008, 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 com.sun.tools.javac.code.Type;

 import com.sun.tools.javac.util.Name;

 /** A JVM class file.

  *

  *  <p>Generic Java classfiles have one additional attribute for classes,

  *  methods and fields:

  *  <pre>

  *   "Signature" (u4 attr-length, u2 signature-index)

  *  </pre>

  *

  *  <p>A signature gives the full Java type of a method or field. When

  *  used as a class attribute, it indicates type parameters, followed

  *  by supertype, followed by all interfaces.

  *  <pre>

  *     methodOrFieldSignature ::= type

  *     classSignature         ::= [ typeparams ] supertype { interfacetype }

  *  </pre>

  *  <p>The type syntax in signatures is extended as follows:

  *  <pre>

  *     type       ::= ... | classtype | methodtype | typevar

  *     classtype  ::= classsig { '.' classsig }

  *     classig    ::= 'L' name [typeargs] ';'

  *     methodtype ::= [ typeparams ] '(' { type } ')' type

  *     typevar    ::= 'T' name ';'

  *     typeargs   ::= '<' type { type } '>'

  *     typeparams ::= '<' typeparam { typeparam } '>'

  *     typeparam  ::= name ':' type

  *  </pre>

  *  <p>This class defines constants used in class files as well

  *  as routines to convert between internal ``.'' and external ``/''

  *  separators in class names.

  *

  *  <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 ClassFile {

     public final static int JAVA_MAGIC = 0xCAFEBABE;

     // see Target

     public final static int CONSTANT_Utf8 = 1;

     public final static int CONSTANT_Unicode = 2;

     public final static int CONSTANT_Integer = 3;

     public final static int CONSTANT_Float = 4;

     public final static int CONSTANT_Long = 5;

     public final static int CONSTANT_Double = 6;

     public final static int CONSTANT_Class = 7;

     public final static int CONSTANT_String = 8;

     public final static int CONSTANT_Fieldref = 9;

     public final static int CONSTANT_Methodref = 10;

     public final static int CONSTANT_InterfaceMethodref = 11;

     public final static int CONSTANT_NameandType = 12;

     public final static int MAX_PARAMETERS = 0xff;

     public final static int MAX_DIMENSIONS = 0xff;

     public final static int MAX_CODE = 0xffff;

     public final static int MAX_LOCALS = 0xffff;

     public final static int MAX_STACK = 0xffff;

     public enum Version {

         V45_3(45, 3), // base level for all attributes

         V49(49, 0),   // JDK 1.5: enum, generics, annotations

         V50(50, 0),   // JDK 1.6: stackmaps

         V51(51, 0);   // JDK 1.7

         Version(int major, int minor) {

             this.major = major;

             this.minor = minor;

         }

         public final int major, minor;

     }

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

  * String Translation Routines

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

     /** Return internal representation of buf[offset..offset+len-1],

      *  converting '/' to '.'.

      */

     public static byte[] internalize(byte[] buf, int offset, int len) {

         byte[] translated = new byte[len];

         for (int j = 0; j < len; j++) {

             byte b = buf[offset + j];

             if (b == '/') translated[j] = (byte) '.';

             else translated[j] = b;

         }

         return translated;

     }

     /** Return internal representation of given name,

      *  converting '/' to '.'.

      */

     public static byte[] internalize(Name name) {

         return internalize(name.getByteArray(), name.getByteOffset(), name.getByteLength());

     }

     /** Return external representation of buf[offset..offset+len-1],

      *  converting '.' to '/'.

      */

     public static byte[] externalize(byte[] buf, int offset, int len) {

         byte[] translated = new byte[len];

         for (int j = 0; j < len; j++) {

             byte b = buf[offset + j];

             if (b == '.') translated[j] = (byte) '/';

             else translated[j] = b;

         }

         return translated;

     }

     /** Return external representation of given name,

      *  converting '/' to '.'.

      */

     public static byte[] externalize(Name name) {

         return externalize(name.getByteArray(), name.getByteOffset(), name.getByteLength());

     }

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

  * Name-and-type

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

     /** A class for the name-and-type signature of a method or field.

      */

     public static class NameAndType {

         Name name;

         Type type;

         NameAndType(Name name, Type type) {

             this.name = name;

             this.type = type;

         }

         public boolean equals(Object other) {

             return

                 other instanceof NameAndType &&

                 name == ((NameAndType) other).name &&

                 type.equals(((NameAndType) other).type);

         }

         public int hashCode() {

             return name.hashCode() * type.hashCode();

         }

     }

 }