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/*
 * 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 com.feilong.lib.javassist.bytecode;

import java.io.PrintWriter;
import java.util.List;

import com.feilong.lib.javassist.Modifier;

/**
 * A utility class for priting the contents of a class file.
 * It prints a constant pool table, fields, and methods in a
 * human readable representation.
 */
public class ClassFilePrinter{

    /**
     * Prints the contents of a class file to the standard output stream.
     */
    public static void print(ClassFile cf){
        print(cf, new PrintWriter(System.out, true));
    }

    /**
     * Prints the contents of a class file.
     */
    public static void print(ClassFile cf,PrintWriter out){
        /*
         * 0x0020 (SYNCHRONIZED) means ACC_SUPER if the modifiers
         * are of a class.
         */
        int mod = AccessFlag.toModifier(cf.getAccessFlags() & ~AccessFlag.SYNCHRONIZED);
        out.println("major: " + cf.major + ", minor: " + cf.minor + " modifiers: " + Integer.toHexString(cf.getAccessFlags()));
        out.println(Modifier.toString(mod) + " class " + cf.getName() + " extends " + cf.getSuperclass());

        String[] infs = cf.getInterfaces();
        if (infs != null && infs.length > 0){
            out.print("    implements ");
            out.print(infs[0]);
            for (int i = 1; i < infs.length; ++i){
                out.print(", " + infs[i]);
            }

            out.println();
        }

        out.println();
        List fields = cf.getFields();
        for (FieldInfo finfo : fields){
            int acc = finfo.getAccessFlags();
            out.println(Modifier.toString(AccessFlag.toModifier(acc)) + " " + finfo.getName() + "\t" + finfo.getDescriptor());
            printAttributes(finfo.getAttributes(), out, 'f');
        }

        out.println();
        List methods = cf.getMethods();
        for (MethodInfo minfo : methods){
            int acc = minfo.getAccessFlags();
            out.println(Modifier.toString(AccessFlag.toModifier(acc)) + " " + minfo.getName() + "\t" + minfo.getDescriptor());
            printAttributes(minfo.getAttributes(), out, 'm');
            out.println();
        }

        out.println();
        printAttributes(cf.getAttributes(), out, 'c');
    }

    static void printAttributes(List list,PrintWriter out,char kind){
        if (list == null){
            return;
        }

        for (AttributeInfo ai : list){
            if (ai instanceof CodeAttribute){
                CodeAttribute ca = (CodeAttribute) ai;
                out.println("attribute: " + ai.getName() + ": " + ai.getClass().getName());
                out.println(
                                "max stack " + ca.getMaxStack() + ", max locals " + ca.getMaxLocals() + ", " + ca.getExceptionTable().size()
                                                + " catch blocks");
                out.println("");
                printAttributes(ca.getAttributes(), out, kind);
                out.println("");
            }else if (ai instanceof AnnotationsAttribute){
                out.println("annnotation: " + ai.toString());
            }else if (ai instanceof ParameterAnnotationsAttribute){
                out.println("parameter annnotations: " + ai.toString());
            }else if (ai instanceof StackMapTable){
                out.println("");
                StackMapTable.Printer.print((StackMapTable) ai, out);
                out.println("");
            }else if (ai instanceof StackMap){
                out.println("");
                ((StackMap) ai).print(out);
                out.println("");
            }else if (ai instanceof SignatureAttribute){
                SignatureAttribute sa = (SignatureAttribute) ai;
                String sig = sa.getSignature();
                out.println("signature: " + sig);
                try{
                    String s;
                    if (kind == 'c'){
                        s = SignatureAttribute.toClassSignature(sig).toString();
                    }else if (kind == 'm'){
                        s = SignatureAttribute.toMethodSignature(sig).toString();
                    }else{
                        s = SignatureAttribute.toFieldSignature(sig).toString();
                    }

                    out.println("           " + s);
                }catch (BadBytecode e){
                    out.println("           syntax error");
                }
            }else{
                out.println("attribute: " + ai.getName() + " (" + ai.get().length + " byte): " + ai.getClass().getName());
            }
        }
    }
}