/***
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000-2005 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.drools.asm.util;
import java.io.FileInputStream;
import java.io.PrintWriter;
import org.drools.asm.AnnotationVisitor;
import org.drools.asm.Attribute;
import org.drools.asm.ClassReader;
import org.drools.asm.ClassVisitor;
import org.drools.asm.FieldVisitor;
import org.drools.asm.MethodVisitor;
import org.drools.asm.Opcodes;
import org.drools.asm.signature.SignatureReader;
/**
* A {@link ClassVisitor} that prints a disassembled view of the classes it
* visits. This class visitor can be used alone (see the {@link #main main}
* method) to disassemble a class. It can also be used in the middle of class
* visitor chain to trace the class that is visited at a given point in this
* chain. This may be uselful for debugging purposes. <p> The trace printed when
* visiting the <tt>Hello</tt> class is the following: <p> <blockquote>
*
* <pre>
* // class version 49.0 (49)
* // access flags 33
* public class Hello {
*
* // compiled from: Hello.java
*
* // access flags 1
* public <init> ()V
* ALOAD 0
* INVOKESPECIAL java/lang/Object <init> ()V
* RETURN
* MAXSTACK = 1
* MAXLOCALS = 1
*
* // access flags 9
* public static main ([Ljava/lang/String;)V
* GETSTATIC java/lang/System out Ljava/io/PrintStream;
* LDC "hello"
* INVOKEVIRTUAL java/io/PrintStream println (Ljava/lang/String;)V
* RETURN
* MAXSTACK = 2
* MAXLOCALS = 1
* }
* </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
* @author Eugene Kuleshov
*/
public class TraceClassVisitor extends TraceAbstractVisitor
implements
ClassVisitor {
/**
* The {@link ClassVisitor} to which this visitor delegates calls. May be
* <tt>null</tt>.
*/
protected final ClassVisitor cv;
/**
* The print writer to be used to print the class.
*/
protected final PrintWriter pw;
/**
* Prints a disassembled view of the given class to the standard output. <p>
* Usage: TraceClassVisitor [-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 {
int i = 0;
boolean skipDebug = true;
boolean ok = true;
if ( args.length < 1 || args.length > 2 ) {
ok = false;
}
if ( ok && args[0].equals( "-debug" ) ) {
i = 1;
skipDebug = false;
if ( args.length != 2 ) {
ok = false;
}
}
if ( !ok ) {
System.err.println( "Prints a disassembled view of the given class." );
System.err.println( "Usage: TraceClassVisitor [-debug] " + "<fully qualified class name or class file name>" );
return;
}
ClassReader cr;
if ( args[i].endsWith( ".class" ) || args[i].indexOf( '\\' ) > -1 || args[i].indexOf( '/' ) > -1 ) {
cr = new ClassReader( new FileInputStream( args[i] ) );
} else {
cr = new ClassReader( args[i] );
}
cr.accept( new TraceClassVisitor( new PrintWriter( System.out ) ),
getDefaultAttributes(),
skipDebug );
}
/**
* Constructs a new {@link TraceClassVisitor}.
*
* @param pw the print writer to be used to print the class.
*/
public TraceClassVisitor(final PrintWriter pw) {
this( null,
pw );
}
/**
* Constructs a new {@link TraceClassVisitor}.
*
* @param cv the {@link ClassVisitor} to which this visitor delegates calls.
* May be <tt>null</tt>.
* @param pw the print writer to be used to print the class.
*/
public TraceClassVisitor(final ClassVisitor cv,
final PrintWriter pw) {
this.cv = cv;
this.pw = pw;
}
// ------------------------------------------------------------------------
// Implementation of the ClassVisitor interface
// ------------------------------------------------------------------------
public void visit(final int version,
final int access,
final String name,
final String signature,
final String superName,
final String[] interfaces) {
final int major = version & 0xFFFF;
final int minor = version >>> 16;
this.buf.setLength( 0 );
this.buf.append( "// class version " ).append( major ).append( '.' ).append( minor ).append( " (" ).append( version ).append( ")\n" );
if ( (access & Opcodes.ACC_DEPRECATED) != 0 ) {
this.buf.append( "// DEPRECATED\n" );
}
this.buf.append( "// access flags " ).append( access ).append( '\n' );
appendDescriptor( TraceAbstractVisitor.CLASS_SIGNATURE,
signature );
if ( signature != null ) {
final TraceSignatureVisitor sv = new TraceSignatureVisitor( access );
final SignatureReader r = new SignatureReader( signature );
r.accept( sv );
this.buf.append( "// declaration: " ).append( name ).append( sv.getDeclaration() ).append( '\n' );
}
appendAccess( access & ~Opcodes.ACC_SUPER );
if ( (access & Opcodes.ACC_ANNOTATION) != 0 ) {
this.buf.append( "@interface " );
} else if ( (access & Opcodes.ACC_INTERFACE) != 0 ) {
this.buf.append( "interface " );
} else if ( (access & Opcodes.ACC_ENUM) != 0 ) {
this.buf.append( "enum " );
} else {
this.buf.append( "class " );
}
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
name );
if ( superName != null && !superName.equals( "java/lang/Object" ) ) {
this.buf.append( " extends " );
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
superName );
this.buf.append( ' ' );
}
if ( interfaces != null && interfaces.length > 0 ) {
this.buf.append( " implements " );
for ( int i = 0; i < interfaces.length; ++i ) {
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
interfaces[i] );
this.buf.append( ' ' );
}
}
this.buf.append( " {\n\n" );
this.text.add( this.buf.toString() );
if ( this.cv != null ) {
this.cv.visit( version,
access,
name,
signature,
superName,
interfaces );
}
}
public void visitSource(final String file,
final String debug) {
this.buf.setLength( 0 );
if ( file != null ) {
this.buf.append( this.tab ).append( "// compiled from: " ).append( file ).append( '\n' );
}
if ( debug != null ) {
this.buf.append( this.tab ).append( "// debug info: " ).append( debug ).append( '\n' );
}
if ( this.buf.length() > 0 ) {
this.text.add( this.buf.toString() );
}
if ( this.cv != null ) {
this.cv.visitSource( file,
debug );
}
}
public void visitOuterClass(final String owner,
final String name,
final String desc) {
this.buf.setLength( 0 );
this.buf.append( this.tab ).append( "OUTERCLASS " );
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
owner );
// if enclosing name is null, so why should we show this info?
if ( name != null ) {
this.buf.append( ' ' ).append( name ).append( ' ' );
} else {
this.buf.append( ' ' );
}
appendDescriptor( TraceAbstractVisitor.METHOD_DESCRIPTOR,
desc );
this.buf.append( '\n' );
this.text.add( this.buf.toString() );
if ( this.cv != null ) {
this.cv.visitOuterClass( owner,
name,
desc );
}
}
public AnnotationVisitor visitAnnotation(final String desc,
final boolean visible) {
this.text.add( "\n" );
final AnnotationVisitor tav = super.visitAnnotation( desc,
visible );
if ( this.cv != null ) {
((TraceAnnotationVisitor) tav).av = this.cv.visitAnnotation( desc,
visible );
}
return tav;
}
public void visitAttribute(final Attribute attr) {
this.text.add( "\n" );
super.visitAttribute( attr );
if ( this.cv != null ) {
this.cv.visitAttribute( attr );
}
}
public void visitInnerClass(final String name,
final String outerName,
final String innerName,
final int access) {
this.buf.setLength( 0 );
this.buf.append( this.tab ).append( "// access flags " ).append( access & ~Opcodes.ACC_SUPER ).append( '\n' );
this.buf.append( this.tab );
appendAccess( access );
this.buf.append( "INNERCLASS " );
if ( (access & Opcodes.ACC_ENUM) != 0 ) {
this.buf.append( "enum " );
}
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
name );
this.buf.append( ' ' );
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
outerName );
this.buf.append( ' ' );
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
innerName );
this.buf.append( '\n' );
this.text.add( this.buf.toString() );
if ( this.cv != null ) {
this.cv.visitInnerClass( name,
outerName,
innerName,
access );
}
}
public FieldVisitor visitField(final int access,
final String name,
final String desc,
final String signature,
final Object value) {
this.buf.setLength( 0 );
this.buf.append( '\n' );
if ( (access & Opcodes.ACC_DEPRECATED) != 0 ) {
this.buf.append( this.tab ).append( "// DEPRECATED\n" );
}
this.buf.append( this.tab ).append( "// access flags " ).append( access ).append( '\n' );
if ( signature != null ) {
this.buf.append( this.tab );
appendDescriptor( TraceAbstractVisitor.FIELD_SIGNATURE,
signature );
final TraceSignatureVisitor sv = new TraceSignatureVisitor( 0 );
final SignatureReader r = new SignatureReader( signature );
r.acceptType( sv );
this.buf.append( this.tab ).append( "// declaration: " ).append( sv.getDeclaration() ).append( '\n' );
}
this.buf.append( this.tab );
appendAccess( access );
if ( (access & Opcodes.ACC_ENUM) != 0 ) {
this.buf.append( "enum " );
}
appendDescriptor( TraceAbstractVisitor.FIELD_DESCRIPTOR,
desc );
this.buf.append( ' ' ).append( name );
if ( value != null ) {
this.buf.append( " = " );
if ( value instanceof String ) {
this.buf.append( "\"" ).append( value ).append( "\"" );
} else {
this.buf.append( value );
}
}
this.buf.append( '\n' );
this.text.add( this.buf.toString() );
final TraceFieldVisitor tav = createTraceFieldVisitor();
this.text.add( tav.getText() );
if ( this.cv != null ) {
tav.fv = this.cv.visitField( access,
name,
desc,
signature,
value );
}
return tav;
}
public MethodVisitor visitMethod(final int access,
final String name,
final String desc,
final String signature,
final String[] exceptions) {
this.buf.setLength( 0 );
this.buf.append( '\n' );
if ( (access & Opcodes.ACC_DEPRECATED) != 0 ) {
this.buf.append( this.tab ).append( "// DEPRECATED\n" );
}
this.buf.append( this.tab ).append( "// access flags " ).append( access ).append( '\n' );
this.buf.append( this.tab );
appendDescriptor( TraceAbstractVisitor.METHOD_SIGNATURE,
signature );
if ( signature != null ) {
final TraceSignatureVisitor v = new TraceSignatureVisitor( 0 );
final SignatureReader r = new SignatureReader( signature );
r.accept( v );
final String genericDecl = v.getDeclaration();
final String genericReturn = v.getReturnType();
final String genericExceptions = v.getExceptions();
this.buf.append( this.tab ).append( "// declaration: " ).append( genericReturn ).append( ' ' ).append( name ).append( genericDecl );
if ( genericExceptions != null ) {
this.buf.append( " throws " ).append( genericExceptions );
}
this.buf.append( '\n' );
}
appendAccess( access );
if ( (access & Opcodes.ACC_NATIVE) != 0 ) {
this.buf.append( "native " );
}
if ( (access & Opcodes.ACC_VARARGS) != 0 ) {
this.buf.append( "varargs " );
}
if ( (access & Opcodes.ACC_BRIDGE) != 0 ) {
this.buf.append( "bridge " );
}
this.buf.append( name );
appendDescriptor( TraceAbstractVisitor.METHOD_DESCRIPTOR,
desc );
if ( exceptions != null && exceptions.length > 0 ) {
this.buf.append( " throws " );
for ( int i = 0; i < exceptions.length; ++i ) {
appendDescriptor( TraceAbstractVisitor.INTERNAL_NAME,
exceptions[i] );
this.buf.append( ' ' );
}
}
this.buf.append( '\n' );
this.text.add( this.buf.toString() );
final TraceMethodVisitor tcv = createTraceMethodVisitor();
this.text.add( tcv.getText() );
if ( this.cv != null ) {
tcv.mv = this.cv.visitMethod( access,
name,
desc,
signature,
exceptions );
}
return tcv;
}
public void visitEnd() {
this.text.add( "}\n" );
printList( this.pw,
this.text );
this.pw.flush();
if ( this.cv != null ) {
this.cv.visitEnd();
}
}
// ------------------------------------------------------------------------
// Utility methods
// ------------------------------------------------------------------------
protected TraceFieldVisitor createTraceFieldVisitor() {
return new TraceFieldVisitor();
}
protected TraceMethodVisitor createTraceMethodVisitor() {
return new TraceMethodVisitor();
}
/**
* Appends a string representation of the given access modifiers to {@link
* #buf buf}.
*
* @param access some access modifiers.
*/
private void appendAccess(final int access) {
if ( (access & Opcodes.ACC_PUBLIC) != 0 ) {
this.buf.append( "public " );
}
if ( (access & Opcodes.ACC_PRIVATE) != 0 ) {
this.buf.append( "private " );
}
if ( (access & Opcodes.ACC_PROTECTED) != 0 ) {
this.buf.append( "protected " );
}
if ( (access & Opcodes.ACC_FINAL) != 0 ) {
this.buf.append( "final " );
}
if ( (access & Opcodes.ACC_STATIC) != 0 ) {
this.buf.append( "static " );
}
if ( (access & Opcodes.ACC_SYNCHRONIZED) != 0 ) {
this.buf.append( "synchronized " );
}
if ( (access & Opcodes.ACC_VOLATILE) != 0 ) {
this.buf.append( "volatile " );
}
if ( (access & Opcodes.ACC_TRANSIENT) != 0 ) {
this.buf.append( "transient " );
}
// if ((access & Constants.ACC_NATIVE) != 0) {
// buf.append("native ");
// }
if ( (access & Opcodes.ACC_ABSTRACT) != 0 ) {
this.buf.append( "abstract " );
}
if ( (access & Opcodes.ACC_STRICT) != 0 ) {
this.buf.append( "strictfp " );
}
if ( (access & Opcodes.ACC_SYNTHETIC) != 0 ) {
this.buf.append( "synthetic " );
}
}
}