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
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
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.analysis;

import org.objectweb.asm.Type;

A Value that is represented by its type in a seven types type system. This type system distinguishes the UNINITIALZED, INT, FLOAT, LONG, DOUBLE, REFERENCE and RETURNADDRESS types. 
Author:
Eric Bruneton/**
 * A {@link Value} that is represented by its type in a seven types type system.
 * This type system distinguishes the UNINITIALZED, INT, FLOAT, LONG, DOUBLE,
 * REFERENCE and RETURNADDRESS types.
 * 
 * @author Eric Bruneton
 */
public class BasicValue implements Value {

    public static final BasicValue UNINITIALIZED_VALUE = new BasicValue(null);

    public static final BasicValue INT_VALUE = new BasicValue(Type.INT_TYPE);

    public static final BasicValue FLOAT_VALUE = new BasicValue(Type.FLOAT_TYPE);

    public static final BasicValue LONG_VALUE = new BasicValue(Type.LONG_TYPE);

    public static final BasicValue DOUBLE_VALUE = new BasicValue(
            Type.DOUBLE_TYPE);

    public static final BasicValue REFERENCE_VALUE = new BasicValue(
            Type.getObjectType("java/lang/Object"));

    public static final BasicValue RETURNADDRESS_VALUE = new BasicValue(
            Type.VOID_TYPE);

    private final Type type;

    public BasicValue(final Type type) {
        this.type = type;
    }

    public Type getType() {
        return type;
    }

    public int getSize() {
        return type == Type.LONG_TYPE || type == Type.DOUBLE_TYPE ? 2 : 1;
    }

    public boolean isReference() {
        return type != null
                && (type.getSort() == Type.OBJECT || type.getSort() == Type.ARRAY);
    }

    @Override
    public boolean equals(final Object value) {
        if (value == this) {
            return true;
        } else if (value instanceof BasicValue) {
            if (type == null) {
                return ((BasicValue) value).type == null;
            } else {
                return type.equals(((BasicValue) value).type);
            }
        } else {
            return false;
        }
    }

    @Override
    public int hashCode() {
        return type == null ? 0 : type.hashCode();
    }

    @Override
    public String toString() {
        if (this == UNINITIALIZED_VALUE) {
            return ".";
        } else if (this == RETURNADDRESS_VALUE) {
            return "A";
        } else if (this == REFERENCE_VALUE) {
            return "R";
        } else {
            return type.getDescriptor();
        }
    }
}