http://asm.objectweb.org/asm-util/: 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.
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modification, are permitted provided that the following conditions
are met:
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   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.
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/***
 * 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;


A reference to a field or a method.

Author:Remi Forax, Eric Bruneton
/**
 * A reference to a field or a method.
 * 
 * @author Remi Forax
 * @author Eric Bruneton
 */
public final class Handle {

    /**
     * The kind of field or method designated by this Handle. Should be
     * {@link Opcodes#H_GETFIELD}, {@link Opcodes#H_GETSTATIC},
     * {@link Opcodes#H_PUTFIELD}, {@link Opcodes#H_PUTSTATIC},
     * {@link Opcodes#H_INVOKEVIRTUAL}, {@link Opcodes#H_INVOKESTATIC},
     * {@link Opcodes#H_INVOKESPECIAL}, {@link Opcodes#H_NEWINVOKESPECIAL} or
     * {@link Opcodes#H_INVOKEINTERFACE}.
     */
    final int tag;

    
The internal name of the class that owns the field or method designated
by this handle.

/**
     * The internal name of the class that owns the field or method designated
     * by this handle.
     */
    final String owner;

    
The name of the field or method designated by this handle.

/**
     * The name of the field or method designated by this handle.
     */
    final String name;

    
The descriptor of the field or method designated by this handle.

/**
     * The descriptor of the field or method designated by this handle.
     */
    final String desc;
    
    
    
Indicate if the owner is an interface or not.

/**
     * Indicate if the owner is an interface or not.
     */
    final boolean itf;

    
Constructs a new field or method handle.

Params:
Deprecated:this constructor has been superseded by Handle(int, String, String, String, boolean).
/**
     * Constructs a new field or method handle.
     * 
     * @param tag
     *            the kind of field or method designated by this Handle. Must be
     *            {@link Opcodes#H_GETFIELD}, {@link Opcodes#H_GETSTATIC},
     *            {@link Opcodes#H_PUTFIELD}, {@link Opcodes#H_PUTSTATIC},
     *            {@link Opcodes#H_INVOKEVIRTUAL},
     *            {@link Opcodes#H_INVOKESTATIC},
     *            {@link Opcodes#H_INVOKESPECIAL},
     *            {@link Opcodes#H_NEWINVOKESPECIAL} or
     *            {@link Opcodes#H_INVOKEINTERFACE}.
     * @param owner
     *            the internal name of the class that owns the field or method
     *            designated by this handle.
     * @param name
     *            the name of the field or method designated by this handle.
     * @param desc
     *            the descriptor of the field or method designated by this
     *            handle.
     *            
     * @deprecated this constructor has been superseded
     *             by {@link #Handle(int, String, String, String, boolean)}.
     */
    @Deprecated
    public Handle(int tag, String owner, String name, String desc) {
        this(tag, owner, name, desc, tag == Opcodes.H_INVOKEINTERFACE);
    }

    
Constructs a new field or method handle.

Params:
/**
     * Constructs a new field or method handle.
     * 
     * @param tag
     *            the kind of field or method designated by this Handle. Must be
     *            {@link Opcodes#H_GETFIELD}, {@link Opcodes#H_GETSTATIC},
     *            {@link Opcodes#H_PUTFIELD}, {@link Opcodes#H_PUTSTATIC},
     *            {@link Opcodes#H_INVOKEVIRTUAL},
     *            {@link Opcodes#H_INVOKESTATIC},
     *            {@link Opcodes#H_INVOKESPECIAL},
     *            {@link Opcodes#H_NEWINVOKESPECIAL} or
     *            {@link Opcodes#H_INVOKEINTERFACE}.
     * @param owner
     *            the internal name of the class that owns the field or method
     *            designated by this handle.
     * @param name
     *            the name of the field or method designated by this handle.
     * @param desc
     *            the descriptor of the field or method designated by this
     *            handle.
     * @param itf
     *            true if the owner is an interface.
     */
    public Handle(int tag, String owner, String name, String desc, boolean itf) {
        this.tag = tag;
        this.owner = owner;
        this.name = name;
        this.desc = desc;
        this.itf = itf;
    }
    
    
Returns the kind of field or method designated by this handle.

Returns:Opcodes.H_GETFIELD, Opcodes.H_GETSTATIC, Opcodes.H_PUTFIELD, Opcodes.H_PUTSTATIC, Opcodes.H_INVOKEVIRTUAL, Opcodes.H_INVOKESTATIC, Opcodes.H_INVOKESPECIAL, Opcodes.H_NEWINVOKESPECIAL or Opcodes.H_INVOKEINTERFACE.
/**
     * Returns the kind of field or method designated by this handle.
     * 
     * @return {@link Opcodes#H_GETFIELD}, {@link Opcodes#H_GETSTATIC},
     *         {@link Opcodes#H_PUTFIELD}, {@link Opcodes#H_PUTSTATIC},
     *         {@link Opcodes#H_INVOKEVIRTUAL}, {@link Opcodes#H_INVOKESTATIC},
     *         {@link Opcodes#H_INVOKESPECIAL},
     *         {@link Opcodes#H_NEWINVOKESPECIAL} or
     *         {@link Opcodes#H_INVOKEINTERFACE}.
     */
    public int getTag() {
        return tag;
    }

    
Returns the internal name of the class that owns the field or method
designated by this handle.

Returns:the internal name of the class that owns the field or method
        designated by this handle.
/**
     * Returns the internal name of the class that owns the field or method
     * designated by this handle.
     * 
     * @return the internal name of the class that owns the field or method
     *         designated by this handle.
     */
    public String getOwner() {
        return owner;
    }

    
Returns the name of the field or method designated by this handle.

Returns:the name of the field or method designated by this handle.
/**
     * Returns the name of the field or method designated by this handle.
     * 
     * @return the name of the field or method designated by this handle.
     */
    public String getName() {
        return name;
    }

    
Returns the descriptor of the field or method designated by this handle.

Returns:the descriptor of the field or method designated by this handle.
/**
     * Returns the descriptor of the field or method designated by this handle.
     * 
     * @return the descriptor of the field or method designated by this handle.
     */
    public String getDesc() {
        return desc;
    }
    
    
Returns true if the owner of the field or method designated
by this handle is an interface.

Returns:true if the owner of the field or method designated
        by this handle is an interface.
/**
     * Returns true if the owner of the field or method designated
     * by this handle is an interface.
     * 
     * @return true if the owner of the field or method designated
     *         by this handle is an interface.
     */
    public boolean isInterface() {
        return itf;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof Handle)) {
            return false;
        }
        Handle h = (Handle) obj;
        return tag == h.tag && itf == h.itf && owner.equals(h.owner)
                && name.equals(h.name) && desc.equals(h.desc);
    }

    @Override
    public int hashCode() {
        return tag + (itf? 64: 0) + owner.hashCode() * name.hashCode() * desc.hashCode();
    }

    
Returns the textual representation of this handle. The textual
representation is:

for a reference to a class:
owner '.' name desc ' ' '(' tag ')'
for a reference to an interface:
owner '.' name desc ' ' '(' tag ' ' itf ')'


. As this format is unambiguous, it can be parsed if necessary.

/**
     * Returns the textual representation of this handle. The textual
     * representation is:
     * 
     * <pre>
     * for a reference to a class:
     * owner '.' name desc ' ' '(' tag ')'
     * for a reference to an interface:
     * owner '.' name desc ' ' '(' tag ' ' itf ')'
     * </pre>
     * 
     * . As this format is unambiguous, it can be parsed if necessary.
     */
    @Override
    public String toString() {
        return owner + '.' + name + desc + " (" + tag + (itf? " itf": "") + ')';
    }
}