http://asm.objectweb.org/asm-tree/: A very small and fast Java bytecode manipulation framework (ObjectWeb)
  • Eric Bruneton
  • Eugene Kuleshov
  • Remi Forax 
ASM: a very small and fast Java bytecode manipulation framework
Copyright (c) 2000-2011 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
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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THE POSSIBILITY OF SUCH DAMAGE.

/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 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 java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.objectweb.asm.MethodVisitor;


A node that represents a bytecode instruction. An instruction can appear at most once in at most one InsnList at a time.

Author:Eric Bruneton
/**
 * A node that represents a bytecode instruction. <i>An instruction can appear
 * at most once in at most one {@link InsnList} at a time</i>.
 * 
 * @author Eric Bruneton
 */
public abstract class AbstractInsnNode {

    
The type of InsnNode instructions. 
/**
     * The type of {@link InsnNode} instructions.
     */
    public static final int INSN = 0;

    
The type of IntInsnNode instructions. 
/**
     * The type of {@link IntInsnNode} instructions.
     */
    public static final int INT_INSN = 1;

    
The type of VarInsnNode instructions. 
/**
     * The type of {@link VarInsnNode} instructions.
     */
    public static final int VAR_INSN = 2;

    
The type of TypeInsnNode instructions. 
/**
     * The type of {@link TypeInsnNode} instructions.
     */
    public static final int TYPE_INSN = 3;

    
The type of FieldInsnNode instructions. 
/**
     * The type of {@link FieldInsnNode} instructions.
     */
    public static final int FIELD_INSN = 4;

    
The type of MethodInsnNode instructions. 
/**
     * The type of {@link MethodInsnNode} instructions.
     */
    public static final int METHOD_INSN = 5;

    
The type of InvokeDynamicInsnNode instructions. 
/**
     * The type of {@link InvokeDynamicInsnNode} instructions.
     */
    public static final int INVOKE_DYNAMIC_INSN = 6;

    
The type of JumpInsnNode instructions. 
/**
     * The type of {@link JumpInsnNode} instructions.
     */
    public static final int JUMP_INSN = 7;

    
The type of LabelNode "instructions". 
/**
     * The type of {@link LabelNode} "instructions".
     */
    public static final int LABEL = 8;

    
The type of LdcInsnNode instructions. 
/**
     * The type of {@link LdcInsnNode} instructions.
     */
    public static final int LDC_INSN = 9;

    
The type of IincInsnNode instructions. 
/**
     * The type of {@link IincInsnNode} instructions.
     */
    public static final int IINC_INSN = 10;

    
The type of TableSwitchInsnNode instructions. 
/**
     * The type of {@link TableSwitchInsnNode} instructions.
     */
    public static final int TABLESWITCH_INSN = 11;

    
The type of LookupSwitchInsnNode instructions. 
/**
     * The type of {@link LookupSwitchInsnNode} instructions.
     */
    public static final int LOOKUPSWITCH_INSN = 12;

    
The type of MultiANewArrayInsnNode instructions. 
/**
     * The type of {@link MultiANewArrayInsnNode} instructions.
     */
    public static final int MULTIANEWARRAY_INSN = 13;

    
The type of FrameNode "instructions". 
/**
     * The type of {@link FrameNode} "instructions".
     */
    public static final int FRAME = 14;

    
The type of LineNumberNode "instructions". 
/**
     * The type of {@link LineNumberNode} "instructions".
     */
    public static final int LINE = 15;

    
The opcode of this instruction.

/**
     * The opcode of this instruction.
     */
    protected int opcode;

    
The runtime visible type annotations of this instruction. This field is only used for real instructions (i.e. not for labels, frames, or line number nodes). This list is a list of TypeAnnotationNode objects. May be null.

@associatesorg.objectweb.asm.tree.TypeAnnotationNode
@labelvisible
/**
     * The runtime visible type annotations of this instruction. This field is
     * only used for real instructions (i.e. not for labels, frames, or line
     * number nodes). This list is a list of {@link TypeAnnotationNode} objects.
     * May be <tt>null</tt>.
     * 
     * @associates org.objectweb.asm.tree.TypeAnnotationNode
     * @label visible
     */
    public List<TypeAnnotationNode> visibleTypeAnnotations;

    
The runtime invisible type annotations of this instruction. This field is only used for real instructions (i.e. not for labels, frames, or line number nodes). This list is a list of TypeAnnotationNode objects. May be null.

@associatesorg.objectweb.asm.tree.TypeAnnotationNode
@labelinvisible
/**
     * The runtime invisible type annotations of this instruction. This field is
     * only used for real instructions (i.e. not for labels, frames, or line
     * number nodes). This list is a list of {@link TypeAnnotationNode} objects.
     * May be <tt>null</tt>.
     * 
     * @associates org.objectweb.asm.tree.TypeAnnotationNode
     * @label invisible
     */
    public List<TypeAnnotationNode> invisibleTypeAnnotations;

    
Previous instruction in the list to which this instruction belongs.

/**
     * Previous instruction in the list to which this instruction belongs.
     */
    AbstractInsnNode prev;

    
Next instruction in the list to which this instruction belongs.

/**
     * Next instruction in the list to which this instruction belongs.
     */
    AbstractInsnNode next;

    
Index of this instruction in the list to which it belongs. The value of this field is correct only when InsnList.cache is not null. A value of -1 indicates that this instruction does not belong to any InsnList. 
/**
     * Index of this instruction in the list to which it belongs. The value of
     * this field is correct only when {@link InsnList#cache} is not null. A
     * value of -1 indicates that this instruction does not belong to any
     * {@link InsnList}.
     */
    int index;

    
Constructs a new AbstractInsnNode. 
Params:
  • opcode – 
           the opcode of the instruction to be constructed.
/**
     * Constructs a new {@link AbstractInsnNode}.
     * 
     * @param opcode
     *            the opcode of the instruction to be constructed.
     */
    protected AbstractInsnNode(final int opcode) {
        this.opcode = opcode;
        this.index = -1;
    }

    
Returns the opcode of this instruction.

Returns:the opcode of this instruction.
/**
     * Returns the opcode of this instruction.
     * 
     * @return the opcode of this instruction.
     */
    public int getOpcode() {
        return opcode;
    }

    
Returns the type of this instruction.

Returns:the type of this instruction, i.e. one the constants defined in
        this class.
/**
     * Returns the type of this instruction.
     * 
     * @return the type of this instruction, i.e. one the constants defined in
     *         this class.
     */
    public abstract int getType();

    
Returns the previous instruction in the list to which this instruction
belongs, if any.

Returns:the previous instruction in the list to which this instruction
        belongs, if any. May be null.
/**
     * Returns the previous instruction in the list to which this instruction
     * belongs, if any.
     * 
     * @return the previous instruction in the list to which this instruction
     *         belongs, if any. May be <tt>null</tt>.
     */
    public AbstractInsnNode getPrevious() {
        return prev;
    }

    
Returns the next instruction in the list to which this instruction
belongs, if any.

Returns:the next instruction in the list to which this instruction
        belongs, if any. May be null.
/**
     * Returns the next instruction in the list to which this instruction
     * belongs, if any.
     * 
     * @return the next instruction in the list to which this instruction
     *         belongs, if any. May be <tt>null</tt>.
     */
    public AbstractInsnNode getNext() {
        return next;
    }

    
Makes the given code visitor visit this instruction.

Params:
  • cv – 
           a code visitor.
/**
     * Makes the given code visitor visit this instruction.
     * 
     * @param cv
     *            a code visitor.
     */
    public abstract void accept(final MethodVisitor cv);

    
Makes the given visitor visit the annotations of this instruction.

Params:
  • mv – 
           a method visitor.
/**
     * Makes the given visitor visit the annotations of this instruction.
     * 
     * @param mv
     *            a method visitor.
     */
    protected final void acceptAnnotations(final MethodVisitor mv) {
        int n = visibleTypeAnnotations == null ? 0 : visibleTypeAnnotations
                .size();
        for (int i = 0; i < n; ++i) {
            TypeAnnotationNode an = visibleTypeAnnotations.get(i);
            an.accept(mv.visitInsnAnnotation(an.typeRef, an.typePath, an.desc,
                    true));
        }
        n = invisibleTypeAnnotations == null ? 0 : invisibleTypeAnnotations
                .size();
        for (int i = 0; i < n; ++i) {
            TypeAnnotationNode an = invisibleTypeAnnotations.get(i);
            an.accept(mv.visitInsnAnnotation(an.typeRef, an.typePath, an.desc,
                    false));
        }
    }

    
Returns a copy of this instruction.

Params:
  • labels – 
           a map from LabelNodes to cloned LabelNodes.
Returns:a copy of this instruction. The returned instruction does not belong to any InsnList.
/**
     * Returns a copy of this instruction.
     * 
     * @param labels
     *            a map from LabelNodes to cloned LabelNodes.
     * @return a copy of this instruction. The returned instruction does not
     *         belong to any {@link InsnList}.
     */
    public abstract AbstractInsnNode clone(
            final Map<LabelNode, LabelNode> labels);

    
Returns the clone of the given label.

Params:
  • label – 
           a label.
  • map – 
           a map from LabelNodes to cloned LabelNodes.
Returns:the clone of the given label.
/**
     * Returns the clone of the given label.
     * 
     * @param label
     *            a label.
     * @param map
     *            a map from LabelNodes to cloned LabelNodes.
     * @return the clone of the given label.
     */
    static LabelNode clone(final LabelNode label,
            final Map<LabelNode, LabelNode> map) {
        return map.get(label);
    }

    
Returns the clones of the given labels.

Params:
  • labels – 
           a list of labels.
  • map – 
           a map from LabelNodes to cloned LabelNodes.
Returns:the clones of the given labels.
/**
     * Returns the clones of the given labels.
     * 
     * @param labels
     *            a list of labels.
     * @param map
     *            a map from LabelNodes to cloned LabelNodes.
     * @return the clones of the given labels.
     */
    static LabelNode[] clone(final List<LabelNode> labels,
            final Map<LabelNode, LabelNode> map) {
        LabelNode[] clones = new LabelNode[labels.size()];
        for (int i = 0; i < clones.length; ++i) {
            clones[i] = map.get(labels.get(i));
        }
        return clones;
    }

    
Clones the annotations of the given instruction into this instruction.

Params:
  • insn – 
           the source instruction.
Returns:this instruction.
/**
     * Clones the annotations of the given instruction into this instruction.
     * 
     * @param insn
     *            the source instruction.
     * @return this instruction.
     */
    protected final AbstractInsnNode cloneAnnotations(
            final AbstractInsnNode insn) {
        if (insn.visibleTypeAnnotations != null) {
            this.visibleTypeAnnotations = new ArrayList<TypeAnnotationNode>();
            for (int i = 0; i < insn.visibleTypeAnnotations.size(); ++i) {
                TypeAnnotationNode src = insn.visibleTypeAnnotations.get(i);
                TypeAnnotationNode ann = new TypeAnnotationNode(src.typeRef,
                        src.typePath, src.desc);
                src.accept(ann);
                this.visibleTypeAnnotations.add(ann);
            }
        }
        if (insn.invisibleTypeAnnotations != null) {
            this.invisibleTypeAnnotations = new ArrayList<TypeAnnotationNode>();
            for (int i = 0; i < insn.invisibleTypeAnnotations.size(); ++i) {
                TypeAnnotationNode src = insn.invisibleTypeAnnotations.get(i);
                TypeAnnotationNode ann = new TypeAnnotationNode(src.typeRef,
                        src.typePath, src.desc);
                src.accept(ann);
                this.invisibleTypeAnnotations.add(ann);
            }
        }
        return this;
    }
}