/***
* ASM examples: examples showing how ASM can be used
* 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.
*/
import org.objectweb.asm.Attribute;
import org.objectweb.asm.ClassAdapter;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.CodeVisitor;
import org.objectweb.asm.Constants;
import org.objectweb.asm.Label;
import org.objectweb.asm.ByteVector;
import org.objectweb.asm.util.TraceClassVisitor;
import java.io.FileOutputStream;
import java.io.PrintWriter;
/**
* @author Eric Bruneton
*/
public class Attributes extends ClassLoader {
public static void main (final String args[]) throws Exception {
// loads the original class and adapts it
ClassReader cr = new ClassReader("CommentAttribute");
ClassWriter cw = new ClassWriter(false);
ClassVisitor cv = new AddCommentClassAdapter(cw);
cr.accept(cv, new Attribute[] { new CommentAttribute("") }, false);
byte[] b = cw.toByteArray();
// stores the adapted class on disk
FileOutputStream fos = new FileOutputStream("CommentAttribute.class.new");
fos.write(b);
fos.close();
// "disassembles" the adapted class
cr = new ClassReader(b);
cv = new TraceClassVisitor(null, new PrintWriter(System.out));
cr.accept(cv, new Attribute[] { new CommentAttribute("") }, false);
}
}
class AddCommentClassAdapter extends ClassAdapter implements Constants {
public AddCommentClassAdapter (final ClassVisitor cv) {
super(cv);
}
public void visit (
final int version,
final int access,
final String name,
final String superName,
final String[] interfaces,
final String sourceFile)
{
super.visit(version, access, name, superName, interfaces, sourceFile);
visitAttribute(new CommentAttribute("this is a class comment"));
}
public void visitField (
final int access,
final String name,
final String desc,
final Object value,
final Attribute attrs)
{
super.visitField(
access,
name,
desc,
value,
new CommentAttribute("this is a field comment", attrs));
}
public CodeVisitor visitMethod (
final int access,
final String name,
final String desc,
final String[] exceptions,
final Attribute attrs)
{
CodeVisitor mv = cv.visitMethod(
access,
name,
desc,
exceptions,
new CommentAttribute("this is a method comment", attrs));
if (mv != null) {
mv.visitAttribute(new CommentAttribute("this is a code comment"));
}
return mv;
}
}
class CommentAttribute extends Attribute {
private String comment;
public CommentAttribute (final String comment) {
super("Comment");
this.comment = comment;
}
public CommentAttribute (final String comment, final Attribute next) {
super("Comment");
this.comment = comment;
this.next = next;
}
public String getComment () {
return comment;
}
protected Attribute read (
ClassReader cr,
int off,
int len,
char[] buf,
int codeOff,
Label[] labels)
{
return new CommentAttribute(cr.readUTF8(off, buf));
}
protected ByteVector write (
ClassWriter cw,
byte[] code,
int len,
int maxStack,
int maxLocals)
{
return new ByteVector().putShort(cw.newUTF8(comment));
}
}