/*
* Javassist, a Java-bytecode translator toolkit.
* Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. Alternatively, the contents of this file may be used under
* the terms of the GNU Lesser General Public License Version 2.1 or later,
* or the Apache License Version 2.0.
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*/
package org.jboss.forge.furnace.proxy.javassist.bytecode.analysis;
import java.io.PrintStream;
import org.jboss.forge.furnace.proxy.javassist.CtClass;
import org.jboss.forge.furnace.proxy.javassist.CtMethod;
import org.jboss.forge.furnace.proxy.javassist.Modifier;
import org.jboss.forge.furnace.proxy.javassist.NotFoundException;
import org.jboss.forge.furnace.proxy.javassist.bytecode.BadBytecode;
import org.jboss.forge.furnace.proxy.javassist.bytecode.CodeAttribute;
import org.jboss.forge.furnace.proxy.javassist.bytecode.CodeIterator;
import org.jboss.forge.furnace.proxy.javassist.bytecode.ConstPool;
import org.jboss.forge.furnace.proxy.javassist.bytecode.Descriptor;
import org.jboss.forge.furnace.proxy.javassist.bytecode.InstructionPrinter;
import org.jboss.forge.furnace.proxy.javassist.bytecode.MethodInfo;
/**
* A utility class for printing a merged view of the frame state and the
* instructions of a method.
*
* @author Jason T. Greene
*/
public final class FramePrinter {
private final PrintStream stream;
/**
* Constructs a bytecode printer.
*/
public FramePrinter(PrintStream stream) {
this.stream = stream;
}
/**
* Prints all the methods declared in the given class.
*/
public static void print(CtClass clazz, PrintStream stream) {
(new FramePrinter(stream)).print(clazz);
}
/**
* Prints all the methods declared in the given class.
*/
public void print(CtClass clazz) {
CtMethod[] methods = clazz.getDeclaredMethods();
for (int i = 0; i < methods.length; i++) {
print(methods[i]);
}
}
private String getMethodString(CtMethod method) {
try {
return Modifier.toString(method.getModifiers()) + " "
+ method.getReturnType().getName() + " " + method.getName()
+ Descriptor.toString(method.getSignature()) + ";";
} catch (NotFoundException e) {
throw new RuntimeException(e);
}
}
/**
* Prints the instructions and the frame states of the given method.
*/
public void print(CtMethod method) {
stream.println("\n" + getMethodString(method));
MethodInfo info = method.getMethodInfo2();
ConstPool pool = info.getConstPool();
CodeAttribute code = info.getCodeAttribute();
if (code == null)
return;
Frame[] frames;
try {
frames = (new Analyzer()).analyze(method.getDeclaringClass(), info);
} catch (BadBytecode e) {
throw new RuntimeException(e);
}
int spacing = String.valueOf(code.getCodeLength()).length();
CodeIterator iterator = code.iterator();
while (iterator.hasNext()) {
int pos;
try {
pos = iterator.next();
} catch (BadBytecode e) {
throw new RuntimeException(e);
}
stream.println(pos + ": " + InstructionPrinter.instructionString(iterator, pos, pool));
addSpacing(spacing + 3);
Frame frame = frames[pos];
if (frame == null) {
stream.println("--DEAD CODE--");
continue;
}
printStack(frame);
addSpacing(spacing + 3);
printLocals(frame);
}
}
private void printStack(Frame frame) {
stream.print("stack [");
int top = frame.getTopIndex();
for (int i = 0; i <= top; i++) {
if (i > 0)
stream.print(", ");
Type type = frame.getStack(i);
stream.print(type);
}
stream.println("]");
}
private void printLocals(Frame frame) {
stream.print("locals [");
int length = frame.localsLength();
for (int i = 0; i < length; i++) {
if (i > 0)
stream.print(", ");
Type type = frame.getLocal(i);
stream.print(type == null ? "empty" : type.toString());
}
stream.println("]");
}
private void addSpacing(int count) {
while (count-- > 0)
stream.print(' ');
}
}