| 1 | /* |
| 2 | * Copyright 1999-2005 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.tools.javac.jvm; |
| 27 | |
| 28 | import com.sun.tools.javac.code.*; |
| 29 | import com.sun.tools.javac.util.*; |
| 30 | |
| 31 | /** A JVM class file. |
| 32 | * |
| 33 | * <p>Generic Java classfiles have one additional attribute for classes, |
| 34 | * methods and fields: |
| 35 | * <pre> |
| 36 | * "Signature" (u4 attr-length, u2 signature-index) |
| 37 | * </pre> |
| 38 | * |
| 39 | * <p>A signature gives the full Java type of a method or field. When |
| 40 | * used as a class attribute, it indicates type parameters, followed |
| 41 | * by supertype, followed by all interfaces. |
| 42 | * <pre> |
| 43 | * methodOrFieldSignature ::= type |
| 44 | * classSignature ::= [ typeparams ] supertype { interfacetype } |
| 45 | * </pre> |
| 46 | * <p>The type syntax in signatures is extended as follows: |
| 47 | * <pre> |
| 48 | * type ::= ... | classtype | methodtype | typevar |
| 49 | * classtype ::= classsig { '.' classsig } |
| 50 | * classig ::= 'L' name [typeargs] ';' |
| 51 | * methodtype ::= [ typeparams ] '(' { type } ')' type |
| 52 | * typevar ::= 'T' name ';' |
| 53 | * typeargs ::= '<' type { type } '>' |
| 54 | * typeparams ::= '<' typeparam { typeparam } '>' |
| 55 | * typeparam ::= name ':' type |
| 56 | * </pre> |
| 57 | * <p>This class defines constants used in class files as well |
| 58 | * as routines to convert between internal ``.'' and external ``/'' |
| 59 | * separators in class names. |
| 60 | * |
| 61 | * <p><b>This is NOT part of any API supported by Sun Microsystems. If |
| 62 | * you write code that depends on this, you do so at your own risk. |
| 63 | * This code and its internal interfaces are subject to change or |
| 64 | * deletion without notice.</b> */ |
| 65 | public class ClassFile { |
| 66 | |
| 67 | public final static int JAVA_MAGIC = 0xCAFEBABE; |
| 68 | |
| 69 | // see Target |
| 70 | public final static int CONSTANT_Utf8 = 1; |
| 71 | public final static int CONSTANT_Unicode = 2; |
| 72 | public final static int CONSTANT_Integer = 3; |
| 73 | public final static int CONSTANT_Float = 4; |
| 74 | public final static int CONSTANT_Long = 5; |
| 75 | public final static int CONSTANT_Double = 6; |
| 76 | public final static int CONSTANT_Class = 7; |
| 77 | public final static int CONSTANT_String = 8; |
| 78 | public final static int CONSTANT_Fieldref = 9; |
| 79 | public final static int CONSTANT_Methodref = 10; |
| 80 | public final static int CONSTANT_InterfaceMethodref = 11; |
| 81 | public final static int CONSTANT_NameandType = 12; |
| 82 | |
| 83 | public final static int MAX_PARAMETERS = 0xff; |
| 84 | public final static int MAX_DIMENSIONS = 0xff; |
| 85 | public final static int MAX_CODE = 0xffff; |
| 86 | public final static int MAX_LOCALS = 0xffff; |
| 87 | public final static int MAX_STACK = 0xffff; |
| 88 | |
| 89 | |
| 90 | /************************************************************************ |
| 91 | * String Translation Routines |
| 92 | ***********************************************************************/ |
| 93 | |
| 94 | /** Return internal representation of buf[offset..offset+len-1], |
| 95 | * converting '/' to '.'. |
| 96 | */ |
| 97 | public static byte[] internalize(byte[] buf, int offset, int len) { |
| 98 | byte[] translated = new byte[len]; |
| 99 | for (int j = 0; j < len; j++) { |
| 100 | byte b = buf[offset + j]; |
| 101 | if (b == '/') translated[j] = (byte) '.'; |
| 102 | else translated[j] = b; |
| 103 | } |
| 104 | return translated; |
| 105 | } |
| 106 | |
| 107 | /** Return internal representation of given name, |
| 108 | * converting '/' to '.'. |
| 109 | */ |
| 110 | public static byte[] internalize(Name name) { |
| 111 | return internalize(name.table.names, name.index, name.len); |
| 112 | } |
| 113 | |
| 114 | /** Return external representation of buf[offset..offset+len-1], |
| 115 | * converting '.' to '/'. |
| 116 | */ |
| 117 | public static byte[] externalize(byte[] buf, int offset, int len) { |
| 118 | byte[] translated = new byte[len]; |
| 119 | for (int j = 0; j < len; j++) { |
| 120 | byte b = buf[offset + j]; |
| 121 | if (b == '.') translated[j] = (byte) '/'; |
| 122 | else translated[j] = b; |
| 123 | } |
| 124 | return translated; |
| 125 | } |
| 126 | |
| 127 | /** Return external representation of given name, |
| 128 | * converting '/' to '.'. |
| 129 | */ |
| 130 | public static byte[] externalize(Name name) { |
| 131 | return externalize(name.table.names, name.index, name.len); |
| 132 | } |
| 133 | |
| 134 | /************************************************************************ |
| 135 | * Name-and-type |
| 136 | ***********************************************************************/ |
| 137 | |
| 138 | /** A class for the name-and-type signature of a method or field. |
| 139 | */ |
| 140 | public static class NameAndType { |
| 141 | Name name; |
| 142 | Type type; |
| 143 | |
| 144 | NameAndType(Name name, Type type) { |
| 145 | this.name = name; |
| 146 | this.type = type; |
| 147 | } |
| 148 | |
| 149 | public boolean equals(Object other) { |
| 150 | return |
| 151 | other instanceof NameAndType && |
| 152 | name == ((NameAndType) other).name && |
| 153 | type.equals(((NameAndType) other).type); |
| 154 | } |
| 155 | |
| 156 | public int hashCode() { |
| 157 | return name.hashCode() * type.hashCode(); |
| 158 | } |
| 159 | } |
| 160 | } |