/*
 * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.oracle.graal.api.meta;

import java.io.*;

/**
 * Abstract base class for values manipulated by the compiler. All values have a {@linkplain Kind
 * kind} and are immutable.
 */
public abstract class Value implements Serializable {

    private static final long serialVersionUID = -6909397188697766469L;

    @SuppressWarnings("serial") public static final AllocatableValue ILLEGAL = new AllocatableValue(Kind.Illegal) {

        @Override
        public String toString() {
            return "-";
        }
    };

    private final Kind kind;
    private final PlatformKind platformKind;

    /**
     * Initializes a new value of the specified kind.
     * 
     * @param platformKind the kind
     */
    protected Value(PlatformKind platformKind) {
        this.platformKind = platformKind;
        if (platformKind instanceof Kind) {
            this.kind = (Kind) platformKind;
        } else {
            this.kind = Kind.Illegal;
        }
    }

    /**
     * Returns a String representation of the kind, which should be the end of all
     * {@link #toString()} implementation of subclasses.
     */
    protected final String getKindSuffix() {
        return "|" + getKind().getTypeChar();
    }

    /**
     * Returns the kind of this value.
     */
    public final Kind getKind() {
        return kind;
    }

    /**
     * Returns the platform specific kind used to store this value.
     */
    public final PlatformKind getPlatformKind() {
        return platformKind;
    }

    @Override
    public int hashCode() {
        return 41 + platformKind.hashCode();
    }

    @Override
    public boolean equals(Object obj) {
        if (obj instanceof Value) {
            Value other = (Value) obj;
            return kind.equals(other.kind) && platformKind.equals(platformKind);
        }
        return false;
    }
}