/*
* Copyright (c) 1999, 2016, 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.code.Types;
import com.sun.tools.javac.code.Types.UniqueType;
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>{@literal
* 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 CONSTANT_MethodHandle = 15;
public final static int CONSTANT_MethodType = 16;
public final static int CONSTANT_InvokeDynamic = 18;
public final static int REF_getField = 1;
public final static int REF_getStatic = 2;
public final static int REF_putField = 3;
public final static int REF_putStatic = 4;
public final static int REF_invokeVirtual = 5;
public final static int REF_invokeStatic = 6;
public final static int REF_invokeSpecial = 7;
public final static int REF_newInvokeSpecial = 8;
public final static int REF_invokeInterface = 9;
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
V52(52, 0), // JDK 1.8: lambda, type annos, param names
V53(53, 0); // JDK 1.9: modules, indy string concat
Version(int major, int minor) {
this.major = major;
this.minor = minor;
}
public final int major, minor;
private static final Version MIN = values()[0];
/** Return the least version supported, MIN */
public static Version MIN() { return MIN; }
private static final Version MAX = values()[values().length-1];
/** Return the largest version supported, MAX */
public static Version MAX() { return MAX; }
}
/************************************************************************
* String Translation Routines
***********************************************************************/
/**
* Return internal representation of buf[offset..offset+len-1], converting '/' to '.'.
*
* Note: the naming is the inverse of that used by JVMS 4.2 The Internal Form Of Names,
* which defines "internal name" to be the form using "/" instead of "."
*/
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 '.'.
*
* Note: the naming is the inverse of that used by JVMS 4.2 The Internal Form Of Names,
* which defines "internal name" to be the form using "/" instead of "."
*/
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 '/'.
*
* Note: the naming is the inverse of that used by JVMS 4.2 The Internal Form Of Names,
* which defines "internal name" to be the form using "/" instead of "."
*/
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 '.'.
*
* Note: the naming is the inverse of that used by JVMS 4.2 The Internal Form Of Names,
* which defines "internal name" to be the form using "/" instead of "."
*/
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;
UniqueType uniqueType;
Types types;
NameAndType(Name name, Type type, Types types) {
this.name = name;
this.uniqueType = new UniqueType(type, types);
this.types = types;
}
void setType(Type type) {
this.uniqueType = new UniqueType(type, types);
}
@Override
public boolean equals(Object other) {
return (other instanceof NameAndType &&
name == ((NameAndType) other).name &&
uniqueType.equals(((NameAndType) other).uniqueType));
}
@Override
public int hashCode() {
return name.hashCode() * uniqueType.hashCode();
}
}
}