/***
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000,2002,2003 INRIA, France Telecom
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.eclipse.persistence.internal.libraries.asm.util;
import java.io.FileInputStream;
import java.io.PrintWriter;
import org.eclipse.persistence.internal.libraries.asm.Attribute;
import org.eclipse.persistence.internal.libraries.asm.ClassReader;
import org.eclipse.persistence.internal.libraries.asm.CodeVisitor;
import org.eclipse.persistence.internal.libraries.asm.Constants;
import org.eclipse.persistence.internal.libraries.asm.Type;
import org.eclipse.persistence.internal.libraries.asm.util.attrs.ASMifiable;
/**
* A {@link PrintClassVisitor PrintClassVisitor} that prints the ASM code that
* generates the classes it visits. This class visitor can be used to quickly
* write ASM code to generate some given bytecode:
* <ul>
* <li>write the Java source code equivalent to the bytecode you want to
* generate;</li>
* <li>compile it with <tt>javac</tt>;</li>
* <li>make a {@link ASMifierClassVisitor} visit this compiled
* class (see the {@link #main main} method);</li>
* <li>edit the generated source code, if necessary.</li>
* </ul>
* The source code printed when visiting the <tt>Hello</tt> class is the
* following:
* <p>
* <blockquote>
* <pre>
* import org.eclipse.persistence.internal.libraries.asm.*;
* import java.io.FileOutputStream;
*
* public class Dump implements Constants {
*
* public static void main (String[] args) throws Exception {
*
* ClassWriter cw = new ClassWriter(false);
* CodeVisitor cv;
*
* cw.visit(ACC_PUBLIC + ACC_SUPER, "Hello", "java/lang/Object", null, "Hello.java");
*
* {
* cv = cw.visitMethod(ACC_PUBLIC + ACC_STATIC, "main", "([Ljava/lang/String;)V", null, null);
* cv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
* cv.visitLdcInsn("hello");
* cv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V");
* cv.visitInsn(RETURN);
* cv.visitMaxs(2, 1);
* }
* {
* cv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
* cv.visitVarInsn(ALOAD, 0);
* cv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
* cv.visitInsn(RETURN);
* cv.visitMaxs(1, 1);
* }
* cw.visitEnd();
*
* FileOutputStream os = new FileOutputStream("Dumped.class");
* os.write(cw.toByteArray());
* os.close();
* }
* }
* </pre>
* </blockquote>
* where <tt>Hello</tt> is defined by:
* <p>
* <blockquote>
* <pre>
* public class Hello {
*
* public static void main (String[] args) {
* System.out.println("hello");
* }
* }
* </pre>
* </blockquote>
*
* @author Eric Bruneton, Eugene Kuleshov
*/
public class ASMifierClassVisitor extends PrintClassVisitor {
private static final int ACCESS_CLASS = 262144;
private static final int ACCESS_FIELD = 524288;
private static final int ACCESS_INNER = 1048576;
/**
* Prints the ASM source code to generate the given class to the standard
* output.
* <p>
* Usage: ASMifierClassVisitor [-debug]
* <fully qualified class name or class file name>
*
* @param args the command line arguments.
*
* @throws Exception if the class cannot be found, or if an IO exception
* occurs.
*/
public static void main (final String[] args) throws Exception {
if (args.length < 1 || args.length > 2) {
printUsage();
}
int i = 0;
boolean skipDebug = true;
if (args[0].equals("-debug")) {
i = 1;
skipDebug = false;
if (args.length != 2) {
printUsage();
}
}
ClassReader cr;
if (args[i].endsWith(".class")) {
cr = new ClassReader(new FileInputStream(args[i]));
} else {
cr = new ClassReader(args[i]);
}
cr.accept(new ASMifierClassVisitor(
new PrintWriter(System.out)), getDefaultAttributes(), skipDebug);
}
private static void printUsage () {
System.err.println("Prints the ASM code to generate the given class.");
System.err.println("Usage: ASMifierClassVisitor [-debug] " +
"<fully qualified class name or class file name>");
System.exit(-1);
}
/**
* Constructs a new {@link ASMifierClassVisitor} object.
*
* @param pw the print writer to be used to print the class.
*/
public ASMifierClassVisitor (final PrintWriter pw) {
super(pw);
}
public void visit (
final int version,
final int access,
final String name,
final String superName,
final String[] interfaces,
final String sourceFile)
{
int n = name.lastIndexOf( "/");
if( n>-1) {
text.add("package asm."+name.substring( 0, n).replace( '/', '.')+";\n");
}
text.add("import org.eclipse.persistence.internal.libraries.asm.*;\n");
text.add("import org.eclipse.persistence.internal.libraries.asm.attrs.*;\n");
text.add("import java.util.*;\n\n");
text.add("public class "+(n==-1 ? name : name.substring( n+1))+"Dump implements Constants {\n\n");
text.add("public static byte[] dump () throws Exception {\n\n");
text.add("ClassWriter cw = new ClassWriter(false);\n");
text.add("CodeVisitor cv;\n\n");
buf.setLength(0);
buf.append("cw.visit(");
switch(version) {
case Constants.V1_1:
buf.append("V1_1");
break;
case Constants.V1_2:
buf.append("V1_2");
break;
case Constants.V1_3:
buf.append("V1_3");
break;
case Constants.V1_4:
buf.append("V1_4");
break;
case Constants.V1_5:
buf.append("V1_5");
break;
default:
buf.append(version);
break;
}
buf.append(", ");
appendAccess(access | ACCESS_CLASS);
buf.append(", ");
appendConstant(buf, name);
buf.append(", ");
appendConstant(buf, superName);
buf.append(", ");
if (interfaces != null && interfaces.length > 0) {
buf.append("new String[] {");
for (int i = 0; i < interfaces.length; ++i) {
buf.append(i == 0 ? " " : ", ");
appendConstant(buf, interfaces[i]);
}
buf.append(" }");
} else {
buf.append("null");
}
buf.append(", ");
appendConstant(buf, sourceFile);
buf.append(");\n\n");
text.add(buf.toString());
}
public void visitInnerClass (
final String name,
final String outerName,
final String innerName,
final int access)
{
buf.setLength(0);
buf.append("cw.visitInnerClass(");
appendConstant(buf, name);
buf.append(", ");
appendConstant(buf, outerName);
buf.append(", ");
appendConstant(buf, innerName);
buf.append(", ");
appendAccess(access | ACCESS_INNER);
buf.append(");\n\n");
text.add(buf.toString());
}
public void visitField (
final int access,
final String name,
final String desc,
final Object value,
final Attribute attrs)
{
buf.setLength(0);
int n = 1;
if (attrs != null) {
buf.append("{\n");
buf.append("// FIELD ATTRIBUTES\n");
Attribute a = attrs;
while (a != null) {
if (a instanceof ASMifiable) {
((ASMifiable)a).asmify(buf, "fieldAttrs" + n, null);
if (n > 1) {
buf.append("fieldAttrs" + (n - 1) + " = fieldAttrs" + n + ";\n");
}
n++;
} else {
buf.append("// WARNING! skipped non standard field attribute of type ");
buf.append(a.type).append("\n");
}
a = a.next;
}
}
buf.append("cw.visitField(");
appendAccess(access | ACCESS_FIELD);
buf.append(", ");
appendConstant(buf, name);
buf.append(", ");
appendConstant(buf, desc);
buf.append(", ");
appendConstant(buf, value);
if (n==1) {
buf.append(", null);\n\n");
} else {
buf.append(", fieldAttrs1);\n");
buf.append("}\n\n");
}
text.add(buf.toString());
}
public CodeVisitor visitMethod (
final int access,
final String name,
final String desc,
final String[] exceptions,
final Attribute attrs)
{
buf.setLength(0);
buf.append("{\n");
int n = 1;
if (attrs != null) {
buf.append("// METHOD ATTRIBUTES\n");
Attribute a = attrs;
while (a != null) {
if (a instanceof ASMifiable) {
((ASMifiable)a).asmify(buf, "methodAttrs" + n, null);
if (n > 1) {
buf.append("methodAttrs" + (n - 1) + ".next = methodAttrs" + n + ";\n");
}
n++;
} else {
buf.append("// WARNING! skipped non standard method attribute of type ");
buf.append(a.type).append("\n");
}
a = a.next;
}
}
buf.append("cv = cw.visitMethod(");
appendAccess(access);
buf.append(", ");
appendConstant(buf, name);
buf.append(", ");
appendConstant(buf, desc);
buf.append(", ");
if (exceptions != null && exceptions.length > 0) {
buf.append("new String[] {");
for (int i = 0; i < exceptions.length; ++i) {
buf.append(i == 0 ? " " : ", ");
appendConstant(buf, exceptions[i]);
}
buf.append(" }");
} else {
buf.append("null");
}
if (n==1) {
buf.append(", null);\n");
} else {
buf.append(", methodAttrs1);\n");
}
text.add(buf.toString());
PrintCodeVisitor pcv = new ASMifierCodeVisitor();
text.add(pcv.getText());
text.add("}\n");
return pcv;
}
public void visitAttribute (final Attribute attr) {
buf.setLength(0);
if (attr instanceof ASMifiable) {
buf.append("{\n");
buf.append("// CLASS ATRIBUTE\n");
((ASMifiable)attr).asmify(buf, "attr", null);
buf.append("cw.visitAttribute(attr);\n");
buf.append("}\n");
} else {
buf.append("// WARNING! skipped a non standard class attribute of type \"");
buf.append(attr.type).append("\"\n");
}
text.add(buf.toString());
}
public void visitEnd () {
text.add("cw.visitEnd();\n\n");
// text.add("FileOutputStream os = new FileOutputStream(\"Dumped.class\");\n");
// text.add("os.write(cw.toByteArray());\n");
// text.add("os.close();\n");
text.add("return cw.toByteArray();\n");
text.add("}\n");
text.add("}\n");
super.visitEnd();
}
/**
* Appends a string representation of the given access modifiers to {@link
* #buf buf}.
*
* @param access some access modifiers.
*/
void appendAccess (final int access) {
boolean first = true;
if ((access & Constants.ACC_PUBLIC) != 0) {
buf.append("ACC_PUBLIC");
first = false;
}
if ((access & Constants.ACC_PRIVATE) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_PRIVATE");
first = false;
}
if ((access & Constants.ACC_PROTECTED) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_PROTECTED");
first = false;
}
if ((access & Constants.ACC_FINAL) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_FINAL");
first = false;
}
if ((access & Constants.ACC_STATIC) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_STATIC");
first = false;
}
if ((access & Constants.ACC_SYNCHRONIZED) != 0) {
if (!first) {
buf.append(" + ");
}
if ((access & ACCESS_CLASS) != 0) {
buf.append("ACC_SUPER");
} else {
buf.append("ACC_SYNCHRONIZED");
}
first = false;
}
if ((access & Constants.ACC_VOLATILE) != 0 && (access & ACCESS_FIELD) != 0 ) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_VOLATILE");
first = false;
}
if ((access & Constants.ACC_BRIDGE) != 0 &&
(access & ACCESS_CLASS) == 0 && (access & ACCESS_FIELD) == 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_BRIDGE");
first = false;
}
if ((access & Constants.ACC_VARARGS) != 0 &&
(access & ACCESS_CLASS) == 0 && (access & ACCESS_FIELD) == 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_VARARGS");
first = false;
}
if ((access & Constants.ACC_TRANSIENT) != 0 &&
(access & ACCESS_FIELD) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_TRANSIENT");
first = false;
}
if ((access & Constants.ACC_NATIVE) != 0 &&
(access & ACCESS_CLASS) == 0 &&
(access & ACCESS_FIELD) == 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_NATIVE");
first = false;
}
if ((access & Constants.ACC_ENUM) != 0 &&
((access & ACCESS_CLASS) != 0 ||
(access & ACCESS_FIELD) != 0 ||
(access & ACCESS_INNER) != 0)) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_ENUM");
first = false;
}
if ((access & Constants.ACC_ANNOTATION) != 0 &&
((access & ACCESS_CLASS) != 0)) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_ANNOTATION");
first = false;
}
if ((access & Constants.ACC_ABSTRACT) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_ABSTRACT");
first = false;
}
if ((access & Constants.ACC_INTERFACE) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_INTERFACE");
first = false;
}
if ((access & Constants.ACC_STRICT) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_STRICT");
first = false;
}
if ((access & Constants.ACC_SYNTHETIC) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_SYNTHETIC");
first = false;
}
if ((access & Constants.ACC_DEPRECATED) != 0) {
if (!first) {
buf.append(" + ");
}
buf.append("ACC_DEPRECATED");
first = false;
}
if (first) {
buf.append("0");
}
}
/**
* Appends a string representation of the given constant to the given buffer.
*
* @param buf a string buffer.
* @param cst an {@link java.lang.Integer Integer}, {@link java.lang.Float
* Float}, {@link java.lang.Long Long}, {@link java.lang.Double Double}
* or {@link String String} object. May be <tt>null</tt>.
*/
static void appendConstant (final StringBuffer buf, final Object cst) {
if (cst == null) {
buf.append("null");
} else if (cst instanceof String) {
String s = (String)cst;
buf.append("\"");
for (int i = 0; i < s.length(); ++i) {
char c = s.charAt(i);
if (c == '\n') {
buf.append("\\n");
} else if (c == '\r') {
buf.append("\\r");
} else if (c == '\\') {
buf.append("\\\\");
} else if (c == '"') {
buf.append("\\\"");
} else if( c<0x20 || c>0x7f) {
buf.append( "\\u");
if( c<0x10) {
buf.append( "000");
} else if( c<0x100) {
buf.append( "00");
} else if( c<0x1000) {
buf.append( "0");
}
buf.append( Integer.toString( c, 16));
} else {
buf.append(c);
}
}
buf.append("\"");
} else if (cst instanceof Type) {
buf.append("Type.getType(\"");
buf.append(((Type)cst).getDescriptor());
buf.append("\")");
} else if (cst instanceof Integer) {
buf.append("new Integer(")
.append(cst)
.append(")");
} else if (cst instanceof Float) {
buf.append("new Float(\"")
.append(cst).append("\")");
} else if (cst instanceof Long) {
buf.append("new Long(")
.append(cst)
.append("L)");
} else if (cst instanceof Double) {
buf.append("new Double(\"")
.append(cst).append("\")");
}
}
}