/*

 * Copyright (c) 1997, 2008, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 */

/*

 * The Original Code is HAT. The Initial Developer of the

 * Original Code is Bill Foote, with contributions from others

 * at JavaSoft/Sun.

 */

package com.sun.tools.hat.internal.model;

import java.util.Enumeration;

import java.util.Hashtable;

/**

 *

 * @author      Bill Foote

 */

/**

 * Represents a java "Thing".  A thing is anything that can be the value of

 * a field.  This includes JavaHeapObject, JavaObjectRef, and JavaValue.

 */

public abstract class JavaThing {

    protected JavaThing() {

    }

    /**

     * If this is a forward reference, figure out what it really

     * refers to.

     *

     * @param snapshot  The snapshot this is for

     * @param field     The field this thing represents.  If null, it is

     *                  assumed this thing is an object (and never a value).

     */

    public JavaThing dereference(Snapshot shapshot, JavaField field) {

        return this;

    }

    /**

     * Are we the same type as other?

     *

     * @see JavaObject.isSameTypeAs()

     */

    public boolean isSameTypeAs(JavaThing other) {

        return getClass() == other.getClass();

    }

    /**

     * @return true iff this represents a heap-allocated object

     */

    abstract public boolean isHeapAllocated();

    /**

     * @return the size of this object, in bytes, including VM overhead

     */

    abstract public int getSize();

    /**

     * @return a human-readable string representation of this thing

     */

    abstract public String toString();

    /**

     * Compare our string representation to other's

     * @see java.lang.String.compareTo()

     */

    public int compareTo(JavaThing other) {

        return toString().compareTo(other.toString());

    }

}