tracemethodvisitor.java

asm的源码包 并且包含英文的文档

/***
 * 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.objectweb.asm.util;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Attribute;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.signature.SignatureReader;

import java.util.HashMap;

/**
 * A {@link MethodVisitor} that prints a disassembled view of the methods it
 * visits.
 * 
 * @author Eric Bruneton
 */
public class TraceMethodVisitor extends TraceAbstractVisitor implements
        MethodVisitor
{

    /**
     * The {@link MethodVisitor} to which this visitor delegates calls. May be
     * <tt>null</tt>.
     */
    protected MethodVisitor mv;

    /**
     * Tab for bytecode instructions.
     */
    protected String tab2 = "    ";

    /**
     * Tab for table and lookup switch instructions.
     */
    protected String tab3 = "      ";

    /**
     * Tab for labels.
     */
    protected String ltab = "   ";

    /**
     * The label names. This map associate String values to Label keys.
     */
    protected final HashMap labelNames;

    /**
     * Constructs a new {@link TraceMethodVisitor}.
     */
    public TraceMethodVisitor() {
        this(null);
    }

    /**
     * Constructs a new {@link TraceMethodVisitor}.
     * 
     * @param mv the {@link MethodVisitor} to which this visitor delegates
     *        calls. May be <tt>null</tt>.
     */
    public TraceMethodVisitor(final MethodVisitor mv) {
        this.labelNames = new HashMap();
        this.mv = mv;
    }

    // ------------------------------------------------------------------------
    // Implementation of the MethodVisitor interface
    // ------------------------------------------------------------------------

    public AnnotationVisitor visitAnnotation(
        final String desc,
        final boolean visible)
    {
        AnnotationVisitor av = super.visitAnnotation(desc, visible);
        if (mv != null) {
            ((TraceAnnotationVisitor) av).av = mv.visitAnnotation(desc, visible);
        }
        return av;
    }

    public void visitAttribute(final Attribute attr) {
        buf.setLength(0);
        buf.append(tab).append("ATTRIBUTE ");
        appendDescriptor(-1, attr.type);

        if (attr instanceof Traceable) {
            ((Traceable) attr).trace(buf, labelNames);
        } else {
            buf.append(" : unknown\n");
        }

        text.add(buf.toString());
        if (mv != null) {
            mv.visitAttribute(attr);
        }
    }

    public AnnotationVisitor visitAnnotationDefault() {
        text.add(tab2 + "default=");
        TraceAnnotationVisitor tav = createTraceAnnotationVisitor();
        text.add(tav.getText());
        text.add("\n");
        if (mv != null) {
            tav.av = mv.visitAnnotationDefault();
        }
        return tav;
    }

    public AnnotationVisitor visitParameterAnnotation(
        final int parameter,
        final String desc,
        final boolean visible)
    {
        buf.setLength(0);
        buf.append(tab2).append('@');
        appendDescriptor(FIELD_DESCRIPTOR, desc);
        buf.append('(');
        text.add(buf.toString());
        TraceAnnotationVisitor tav = createTraceAnnotationVisitor();
        text.add(tav.getText());
        text.add(visible ? ") // parameter " : ") // invisible, parameter ");
        text.add(new Integer(parameter));
        text.add("\n");
        if (mv != null) {
            tav.av = mv.visitParameterAnnotation(parameter, desc, visible);
        }
        return tav;
    }

    public void visitCode() {
        if (mv != null) {
            mv.visitCode();
        }
    }

    public void visitFrame(
        final int type,
        final int nLocal,
        final Object[] local,
        final int nStack,
        final Object[] stack)
    {
        buf.setLength(0);
        buf.append(ltab);
        buf.append("FRAME ");
        switch (type) {
            case Opcodes.F_NEW:
            case Opcodes.F_FULL:
                buf.append("FULL [");
                appendFrameTypes(nLocal, local);
                buf.append("] [");
                appendFrameTypes(nStack, stack);
                buf.append("]");
                break;
            case Opcodes.F_APPEND:
                buf.append("APPEND [");
                appendFrameTypes(nLocal, local);
                buf.append("]");
                break;
            case Opcodes.F_CHOP:
                buf.append("CHOP ").append(nLocal);
                break;
            case Opcodes.F_SAME:
                buf.append("SAME");
                break;
            case Opcodes.F_SAME1:
                buf.append("SAME1 ");
                appendFrameTypes(1, stack);
                break;
        }
        buf.append("\n");
        text.add(buf.toString());

        if (mv != null) {
            mv.visitFrame(type, nLocal, local, nStack, stack);
        }
    }

    public void visitInsn(final int opcode) {
        buf.setLength(0);
        buf.append(tab2).append(OPCODES[opcode]).append('\n');
        text.add(buf.toString());

        if (mv != null) {
            mv.visitInsn(opcode);
        }
    }

    public void visitIntInsn(final int opcode, final int operand) {
        buf.setLength(0);
        buf.append(tab2)
                .append(OPCODES[opcode])
                .append(' ')
                .append(opcode == Opcodes.NEWARRAY
                        ? TYPES[operand]
                        : Integer.toString(operand))
                .append('\n');
        text.add(buf.toString());

        if (mv != null) {
            mv.visitIntInsn(opcode, operand);
        }
    }

    public void visitVarInsn(final int opcode, final int var) {
        buf.setLength(0);
        buf.append(tab2)
                .append(OPCODES[opcode])
                .append(' ')
                .append(var)
                .append('\n');
        text.add(buf.toString());

        if (mv != null) {
            mv.visitVarInsn(opcode, var);
        }
    }

    public void visitTypeInsn(final int opcode, final String desc) {
        buf.setLength(0);
        buf.append(tab2).append(OPCODES[opcode]).append(' ');
        if (desc.startsWith("[")) {
            appendDescriptor(FIELD_DESCRIPTOR, desc);
        } else {
            appendDescriptor(INTERNAL_NAME, desc);
        }
        buf.append('\n');
        text.add(buf.toString());

        if (mv != null) {
            mv.visitTypeInsn(opcode, desc);
        }
    }

    public void visitFieldInsn(
        final int opcode,
        final String owner,
        final String name,
        final String desc)
    {
        buf.setLength(0);
        buf.append(tab2).append(OPCODES[opcode]).append(' ');
        appendDescriptor(INTERNAL_NAME, owner);
        buf.append('.').append(name).append(" : ");
        appendDescriptor(FIELD_DESCRIPTOR, desc);
        buf.append('\n');
        text.add(buf.toString());

        if (mv != null) {
            mv.visitFieldInsn(opcode, owner, name, desc);
        }
    }

    public void visitMethodInsn(
        final int opcode,
        final String owner,