001 /*
002 * CDDL HEADER START
003 *
004 * The contents of this file are subject to the terms of the
005 * Common Development and Distribution License, Version 1.0 only
006 * (the "License"). You may not use this file except in compliance
007 * with the License.
008 *
009 * You can obtain a copy of the license at
010 * trunk/opends/resource/legal-notices/OpenDS.LICENSE
011 * or https://OpenDS.dev.java.net/OpenDS.LICENSE.
012 * See the License for the specific language governing permissions
013 * and limitations under the License.
014 *
015 * When distributing Covered Code, include this CDDL HEADER in each
016 * file and include the License file at
017 * trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
018 * add the following below this CDDL HEADER, with the fields enclosed
019 * by brackets "[]" replaced with your own identifying information:
020 * Portions Copyright [yyyy] [name of copyright owner]
021 *
022 * CDDL HEADER END
023 *
024 *
025 * Copyright 2006-2008 Sun Microsystems, Inc.
026 */
027 package org.opends.server.backends.jeb;
028
029 import com.sleepycat.je.DatabaseEntry;
030
031 /**
032 * An integer identifier assigned to each entry in the JE backend.
033 * An entry ID is implemented by this class as a long.
034 * There are static methods to assign monotonically increasing entry IDs,
035 * starting from 1.
036 */
037 public class EntryID implements Comparable<EntryID>
038 {
039 /**
040 * The identifier integer value.
041 */
042 private final Long id;
043
044 /**
045 * The value in database format, created when necessary.
046 */
047 private DatabaseEntry data = null;
048
049 /**
050 * Create a new entry ID object from a given long value.
051 * @param id The long value of the ID.
052 */
053 public EntryID(long id)
054 {
055 this.id = id;
056 }
057
058 /**
059 * Create a new entry ID object from a given Long value.
060 * @param id the Long value of the ID.
061 */
062 public EntryID(Long id)
063 {
064 this.id = id;
065 }
066
067 /**
068 * Create a new entry ID object from a value in database format.
069 * @param databaseEntry The database value of the ID.
070 */
071 public EntryID(DatabaseEntry databaseEntry)
072 {
073 data = databaseEntry;
074 id = JebFormat.entryIDFromDatabase(data.getData());
075 }
076
077 /**
078 * Get the value of the entry ID as a long.
079 * @return The entry ID.
080 */
081 public long longValue()
082 {
083 return id;
084 }
085
086 /**
087 * Get the value of the ID in database format.
088 * @return The value of the ID in database format.
089 */
090 public DatabaseEntry getDatabaseEntry()
091 {
092 if (data == null)
093 {
094 data = new DatabaseEntry();
095 data.setData(JebFormat.entryIDToDatabase(id));
096 }
097 return data;
098 }
099
100 /**
101 * Compares this object with the specified object for order. Returns a
102 * negative integer, zero, or a positive integer as this object is less
103 * than, equal to, or greater than the specified object.<p>
104 * <p/>
105 *
106 * @param that the Object to be compared.
107 * @return a negative integer, zero, or a positive integer as this object
108 * is less than, equal to, or greater than the specified object.
109 * @throws ClassCastException if the specified object's type prevents it
110 * from being compared to this Object.
111 */
112 public int compareTo(EntryID that) throws ClassCastException
113 {
114 return this.id.compareTo(that.id);
115 }
116
117 /**
118 * Indicates whether some other object is "equal to" this one.
119 *
120 * @param that the reference object with which to compare.
121 * @return <code>true</code> if this object is the same as the obj
122 * argument; <code>false</code> otherwise.
123 * @see #hashCode()
124 * @see java.util.Hashtable
125 */
126 @Override public boolean equals(Object that)
127 {
128 if (that == null)
129 {
130 return false;
131 }
132 if (this == that)
133 {
134 return true;
135 }
136 if (!(that instanceof EntryID))
137 {
138 return false;
139 }
140 return this.id.equals(((EntryID)that).id);
141 }
142
143 /**
144 * Returns a hash code value for the object. This method is
145 * supported for the benefit of hashtables such as those provided by
146 * <code>java.util.Hashtable</code>.
147 *
148 * @return a hash code value for this object.
149 * @see java.lang.Object#equals(java.lang.Object)
150 * @see java.util.Hashtable
151 */
152 @Override public int hashCode()
153 {
154 return (int)id.longValue();
155 }
156
157 /**
158 * Get a string representation of this object.
159 * @return A string representation of this object.
160 */
161 public String toString()
162 {
163 return id.toString();
164 }
165 }