/* * Copyright (c) 1999, 2005, 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.*; import com.sun.tools.javac.util.*; /** 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; /************************************************************************ * 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.table.names, name.index, name.len); } /** 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.table.names, name.index, name.len); } /************************************************************************ * 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(); } } }