methodnode.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.tree;

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

import java.util.List;
import java.util.ArrayList;
import java.util.Arrays;

/**
 * A node that represents a method.
 * 
 * @author Eric Bruneton
 */
public class MethodNode extends MemberNode implements MethodVisitor {

    /**
     * The method's access flags (see {@link Opcodes}). This field also
     * indicates if the method is synthetic and/or deprecated.
     */
    public int access;

    /**
     * The method's name.
     */
    public String name;

    /**
     * The method's descriptor (see {@link Type}).
     */
    public String desc;

    /**
     * The method's signature. May be <tt>null</tt>.
     */
    public String signature;

    /**
     * The internal names of the method's exception classes (see
     * {@link Type#getInternalName() getInternalName}). This list is a list of
     * {@link String} objects.
     */
    public List exceptions;

    /**
     * The default value of this annotation interface method. This field must be
     * a {@link Byte}, {@link Boolean}, {@link Character}, {@link Short},
     * {@link Integer}, {@link Long}, {@link Float}, {@link Double},
     * {@link String} or {@link Type}, or an two elements String array (for
     * enumeration values), a {@link AnnotationNode}, or a {@link List} of
     * values of one of the preceding types. May be <tt>null</tt>.
     */
    public Object annotationDefault;

    /**
     * The runtime visible parameter annotations of this method. These lists are
     * lists of {@link AnnotationNode} objects. May be <tt>null</tt>.
     * 
     * @associates org.objectweb.asm.tree.AnnotationNode
     * @label invisible parameters
     */
    public List[] visibleParameterAnnotations;

    /**
     * The runtime invisible parameter annotations of this method. These lists
     * are lists of {@link AnnotationNode} objects. May be <tt>null</tt>.
     * 
     * @associates org.objectweb.asm.tree.AnnotationNode
     * @label visible parameters
     */
    public List[] invisibleParameterAnnotations;

    /**
     * The instructions of this method. This list is a list of
     * {@link AbstractInsnNode} objects.
     * 
     * @associates org.objectweb.asm.tree.AbstractInsnNode
     * @label instructions
     */
    public InsnList instructions;

    /**
     * The try catch blocks of this method. This list is a list of
     * {@link TryCatchBlockNode} objects.
     * 
     * @associates org.objectweb.asm.tree.TryCatchBlockNode
     */
    public List tryCatchBlocks;

    /**
     * The maximum stack size of this method.
     */
    public int maxStack;

    /**
     * The maximum number of local variables of this method.
     */
    public int maxLocals;

    /**
     * The local variables of this method. This list is a list of
     * {@link LocalVariableNode} objects. May be <tt>null</tt>
     * 
     * @associates org.objectweb.asm.tree.LocalVariableNode
     */
    public List localVariables;

    /**
     * Constructs an unitialized {@link MethodNode}.
     */
    public MethodNode() {
        this.instructions = new InsnList();
    }
    
    /**
     * Constructs a new {@link MethodNode}.
     * 
     * @param access the method's access flags (see {@link Opcodes}). This
     *        parameter also indicates if the method is synthetic and/or
     *        deprecated.
     * @param name the method's name.
     * @param desc the method's descriptor (see {@link Type}).
     * @param signature the method's signature. May be <tt>null</tt>.
     * @param exceptions the internal names of the method's exception classes
     *        (see {@link Type#getInternalName() getInternalName}). May be
     *        <tt>null</tt>.
     */
    public MethodNode(
        final int access,
        final String name,
        final String desc,
        final String signature,
        final String[] exceptions)
    {
        this();
        this.access = access;
        this.name = name;
        this.desc = desc;
        this.signature = signature;
        this.exceptions = new ArrayList(exceptions == null
                ? 0
                : exceptions.length);
        boolean isAbstract = (access & Opcodes.ACC_ABSTRACT) != 0;
        if (!isAbstract) {
            this.localVariables = new ArrayList(5);
        }
        this.tryCatchBlocks = new ArrayList();
        if (exceptions != null) {
            this.exceptions.addAll(Arrays.asList(exceptions));
        }
    }

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

    public AnnotationVisitor visitAnnotationDefault() {
        return new AnnotationNode(new ArrayList(0) {
            public boolean add(final Object o) {
                annotationDefault = o;
                return super.add(o);
            }
        });
    }

    public AnnotationVisitor visitParameterAnnotation(
        final int parameter,
        final String desc,
        final boolean visible)
    {
        AnnotationNode an = new AnnotationNode(desc);
        if (visible) {
            if (visibleParameterAnnotations == null) {
                int params = Type.getArgumentTypes(this.desc).length;
                visibleParameterAnnotations = new List[params];
            }
            if (visibleParameterAnnotations[parameter] == null) {
                visibleParameterAnnotations[parameter] = new ArrayList(1);
            }
            visibleParameterAnnotations[parameter].add(an);
        } else {
            if (invisibleParameterAnnotations == null) {
                int params = Type.getArgumentTypes(this.desc).length;
                invisibleParameterAnnotations = new List[params];
            }
            if (invisibleParameterAnnotations[parameter] == null) {
                invisibleParameterAnnotations[parameter] = new ArrayList(1);
            }
            invisibleParameterAnnotations[parameter].add(an);
        }
        return an;
    }

    public void visitCode() {
    }

    public void visitFrame(
        final int type,
        final int nLocal,
        final Object[] local,
        final int nStack,
        final Object[] stack)
    {
        instructions.add(new FrameNode(type, nLocal, local == null
                ? null
                : labelNodes(local), nStack, stack == null
                ? null