1 /*

     2  * Copyright (c) 1997, 2008, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

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

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

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 

    27 /*

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

    29  * Original Code is Bill Foote, with contributions from others

    30  * at JavaSoft/Sun.

    31  */

    32 

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

    34 

    35 import java.util.Enumeration;

    36 import java.util.Hashtable;

    37 

    38 

    39 /**

    40  *

    41  * @author      Bill Foote

    42  */

    43 

    44 

    45 /**

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

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

    48  */

    49 

    50 public abstract class JavaThing {

    51 

    52     protected JavaThing() {

    53     }

    54 

    55     /**

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

    57      * refers to.

    58      *

    59      * @param snapshot  The snapshot this is for

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

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

    62      */

    63     public JavaThing dereference(Snapshot shapshot, JavaField field) {

    64         return this;

    65     }

    66 

    67 

    68     /**

    69      * Are we the same type as other?

    70      *

    71      * @see JavaObject.isSameTypeAs()

    72      */

    73     public boolean isSameTypeAs(JavaThing other) {

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

    75     }

    76     /**

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

    78      */

    79     abstract public boolean isHeapAllocated();

    80 

    81     /**

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

    83      */

    84     abstract public int getSize();

    85 

    86     /**

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

    88      */

    89     abstract public String toString();

    90 

    91     /**

    92      * Compare our string representation to other's

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

    94      */

    95     public int compareTo(JavaThing other) {

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

    97     }

    98 

    99 }