/***
* 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.mvel2.asm.util;
import org.mvel2.asm.*;
import org.mvel2.asm.signature.SignatureReader;
import java.io.FileInputStream;
import java.io.PrintWriter;
/**
* 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>
* <p/>
* <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>
* <p/>
* </blockquote> where <tt>Hello</tt> is defined by: <p> <blockquote>
* <p/>
* <pre>
* public class Hello {
*
* public static void main(String[] args) {
* System.out.println("hello");
* }
* }
* </pre>
* <p/>
* </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;
int flags = ClassReader.SKIP_DEBUG;
boolean ok = true;
if (args.length < 1 || args.length > 2) {
ok = false;
}
if (ok && args[0].equals("-debug")) {
i = 1;
flags = 0;
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(),
flags);
}
/**
* 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) {
int major = version & 0xFFFF;
int minor = version >>> 16;
buf.setLength(0);
buf.append("// class version ")
.append(major)
.append('.')
.append(minor)
.append(" (")
.append(version)
.append(")\n");
if ((access & Opcodes.ACC_DEPRECATED) != 0) {
buf.append("// DEPRECATED\n");
}
buf.append("// access flags ").append(access).append('\n');
appendDescriptor(CLASS_SIGNATURE, signature);
if (signature != null) {
TraceSignatureVisitor sv = new TraceSignatureVisitor(access);
SignatureReader r = new SignatureReader(signature);
r.accept(sv);
buf.append("// declaration: ")
.append(name)
.append(sv.getDeclaration())
.append('\n');
}
appendAccess(access & ~Opcodes.ACC_SUPER);
if ((access & Opcodes.ACC_ANNOTATION) != 0) {
buf.append("@interface ");
}
else if ((access & Opcodes.ACC_INTERFACE) != 0) {
buf.append("interface ");
}
else if ((access & Opcodes.ACC_ENUM) == 0) {
buf.append("class ");
}
appendDescriptor(INTERNAL_NAME, name);
if (superName != null && !superName.equals("java/lang/Object")) {
buf.append(" extends ");
appendDescriptor(INTERNAL_NAME, superName);
buf.append(' ');
}
if (interfaces != null && interfaces.length > 0) {
buf.append(" implements ");
for (int i = 0; i < interfaces.length; ++i) {
appendDescriptor(INTERNAL_NAME, interfaces[i]);
buf.append(' ');
}
}
buf.append(" {\n\n");
text.add(buf.toString());
if (cv != null) {
cv.visit(version, access, name, signature, superName, interfaces);
}
}
public void visitSource(final String file, final String debug) {
buf.setLength(0);
if (file != null) {
buf.append(tab)
.append("// compiled from: ")
.append(file)
.append('\n');
}
if (debug != null) {
buf.append(tab)
.append("// debug info: ")
.append(debug)
.append('\n');
}
if (buf.length() > 0) {
text.add(buf.toString());
}
if (cv != null) {
cv.visitSource(file, debug);
}
}
public void visitOuterClass(
final String owner,
final String name,
final String desc) {
buf.setLength(0);
buf.append(tab).append("OUTERCLASS ");
appendDescriptor(INTERNAL_NAME, owner);
buf.append(' ');
if (name != null) {
buf.append(name).append(' ');
}
appendDescriptor(METHOD_DESCRIPTOR, desc);
buf.append('\n');
text.add(buf.toString());
if (cv != null) {
cv.visitOuterClass(owner, name, desc);
}
}
public AnnotationVisitor visitAnnotation(
final String desc,
final boolean visible) {
text.add("\n");
AnnotationVisitor tav = super.visitAnnotation(desc, visible);
if (cv != null) {
((TraceAnnotationVisitor) tav).av = cv.visitAnnotation(desc,
visible);
}
return tav;
}
public void visitAttribute(final Attribute attr) {
text.add("\n");
super.visitAttribute(attr);
if (cv != null) {
cv.visitAttribute(attr);
}
}
public void visitInnerClass(
final String name,
final String outerName,
final String innerName,
final int access) {
buf.setLength(0);
buf.append(tab).append("// access flags ");
buf.append(access & ~Opcodes.ACC_SUPER).append('\n');
buf.append(tab);
appendAccess(access);
buf.append("INNERCLASS ");
appendDescriptor(INTERNAL_NAME, name);
buf.append(' ');
appendDescriptor(INTERNAL_NAME, outerName);
buf.append(' ');
appendDescriptor(INTERNAL_NAME, innerName);
buf.append('\n');
text.add(buf.toString());
if (cv != null) {
cv.visitInnerClass(name, outerName, innerName, access);
}
}
public FieldVisitor visitField(
final int access,
final String name,
final String desc,
final String signature,
final Object value) {
buf.setLength(0);
buf.append('\n');
if ((access & Opcodes.ACC_DEPRECATED) != 0) {
buf.append(tab).append("// DEPRECATED\n");
}
buf.append(tab).append("// access flags ").append(access).append('\n');
if (signature != null) {
buf.append(tab);
appendDescriptor(FIELD_SIGNATURE, signature);
TraceSignatureVisitor sv = new TraceSignatureVisitor(0);
SignatureReader r = new SignatureReader(signature);
r.acceptType(sv);
buf.append(tab)
.append("// declaration: ")
.append(sv.getDeclaration())
.append('\n');
}
buf.append(tab);
appendAccess(access);
appendDescriptor(FIELD_DESCRIPTOR, desc);
buf.append(' ').append(name);
if (value != null) {
buf.append(" = ");
if (value instanceof String) {
buf.append("\"").append(value).append("\"");
}
else {
buf.append(value);
}
}
buf.append('\n');
text.add(buf.toString());
TraceFieldVisitor tav = createTraceFieldVisitor();
text.add(tav.getText());
if (cv != null) {
tav.fv = 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) {
buf.setLength(0);
buf.append('\n');
if ((access & Opcodes.ACC_DEPRECATED) != 0) {
buf.append(tab).append("// DEPRECATED\n");
}
buf.append(tab).append("// access flags ").append(access).append('\n');
if (signature != null) {
buf.append(tab);
appendDescriptor(METHOD_SIGNATURE, signature);
TraceSignatureVisitor v = new TraceSignatureVisitor(0);
SignatureReader r = new SignatureReader(signature);
r.accept(v);
String genericDecl = v.getDeclaration();
String genericReturn = v.getReturnType();
String genericExceptions = v.getExceptions();
buf.append(tab)
.append("// declaration: ")
.append(genericReturn)
.append(' ')
.append(name)
.append(genericDecl);
if (genericExceptions != null) {
buf.append(" throws ").append(genericExceptions);
}
buf.append('\n');
}
buf.append(tab);
appendAccess(access);
if ((access & Opcodes.ACC_NATIVE) != 0) {
buf.append("native ");
}
if ((access & Opcodes.ACC_VARARGS) != 0) {
buf.append("varargs ");
}
if ((access & Opcodes.ACC_BRIDGE) != 0) {
buf.append("bridge ");
}
buf.append(name);
appendDescriptor(METHOD_DESCRIPTOR, desc);
if (exceptions != null && exceptions.length > 0) {
buf.append(" throws ");
for (int i = 0; i < exceptions.length; ++i) {
appendDescriptor(INTERNAL_NAME, exceptions[i]);
buf.append(' ');
}
}
buf.append('\n');
text.add(buf.toString());
TraceMethodVisitor tcv = createTraceMethodVisitor();
text.add(tcv.getText());
if (cv != null) {
tcv.mv = cv.visitMethod(access, name, desc, signature, exceptions);
}
return tcv;
}
public void visitEnd() {
text.add("}\n");
print(pw);
pw.flush();
if (cv != null) {
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) {
buf.append("public ");
}
if ((access & Opcodes.ACC_PRIVATE) != 0) {
buf.append("private ");
}
if ((access & Opcodes.ACC_PROTECTED) != 0) {
buf.append("protected ");
}
if ((access & Opcodes.ACC_FINAL) != 0) {
buf.append("final ");
}
if ((access & Opcodes.ACC_STATIC) != 0) {
buf.append("static ");
}
if ((access & Opcodes.ACC_SYNCHRONIZED) != 0) {
buf.append("synchronized ");
}
if ((access & Opcodes.ACC_VOLATILE) != 0) {
buf.append("volatile ");
}
if ((access & Opcodes.ACC_TRANSIENT) != 0) {
buf.append("transient ");
}
if ((access & Opcodes.ACC_ABSTRACT) != 0) {
buf.append("abstract ");
}
if ((access & Opcodes.ACC_STRICT) != 0) {
buf.append("strictfp ");
}
if ((access & Opcodes.ACC_ENUM) != 0) {
buf.append("enum ");
}
}
}