001: /* Copyright (C) 2004 - 2007 db4objects Inc. http://www.db4o.com
002:
003: This file is part of the db4o open source object database.
004:
005: db4o is free software; you can redistribute it and/or modify it under
006: the terms of version 2 of the GNU General Public License as published
007: by the Free Software Foundation and as clarified by db4objects' GPL
008: interpretation policy, available at
009: http://www.db4o.com/about/company/legalpolicies/gplinterpretation/
010: Alternatively you can write to db4objects, Inc., 1900 S Norfolk Street,
011: Suite 350, San Mateo, CA 94403, USA.
012:
013: db4o is distributed in the hope that it will be useful, but WITHOUT ANY
014: WARRANTY; without even the implied warranty of MERCHANTABILITY or
015: FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
016: for more details.
017:
018: You should have received a copy of the GNU General Public License along
019: with this program; if not, write to the Free Software Foundation, Inc.,
020: 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
021: package com.db4o.ext;
022:
023: import com.db4o.foundation.*;
024:
025: /**
026: * a unique universal identify for an object. <br><br>The db4o UUID consists of
027: * two parts:<br> - an indexed long for fast access,<br> - the signature of the
028: * {@link com.db4o.ObjectContainer ObjectContainer} the object was created with.
029: * <br><br>Db4oUUIDs are valid representations of objects over multiple
030: * ObjectContainers
031: */
032: public class Db4oUUID {
033:
034: private final long longPart;
035: private final byte[] signaturePart;
036:
037: /**
038: * constructs a Db4oUUID from a long part and a signature part
039: *
040: * @param longPart_ the long part
041: * @param signaturePart_ the signature part
042: */
043: public Db4oUUID(long longPart_, byte[] signaturePart_) {
044: longPart = longPart_;
045: signaturePart = signaturePart_;
046: }
047:
048: /**
049: * returns the long part of this UUID. <br><br>To uniquely identify an object
050: * universally, db4o uses an indexed long and a reference to the
051: * Db4oDatabase object it was created on.
052: *
053: * @return the long part of this UUID.
054: */
055: public long getLongPart() {
056: return longPart;
057: }
058:
059: /**
060: * returns the signature part of this UUID. <br><br> <br><br>To uniquely
061: * identify an object universally, db4o uses an indexed long and a reference to
062: * the Db4oDatabase singleton object of the {@link
063: * com.db4o.ObjectContainer ObjectContainer} it was created on. This method
064: * returns the signature of the Db4oDatabase object of the ObjectContainer: the
065: * signature of the origin ObjectContainer.
066: *
067: * @return the signature of the Db4oDatabase for this UUID.
068: */
069: public byte[] getSignaturePart() {
070: return signaturePart;
071: }
072:
073: public boolean equals(Object o) {
074: if (this == o)
075: return true;
076: if (o == null || getClass() != o.getClass())
077: return false;
078:
079: final Db4oUUID other = (Db4oUUID) o;
080:
081: if (longPart != other.longPart)
082: return false;
083: if (signaturePart == null) {
084: return other.signaturePart == null;
085: }
086: if (signaturePart.length != other.signaturePart.length) {
087: return false;
088: }
089: for (int i = 0; i < signaturePart.length; i++) {
090: if (signaturePart[i] != other.signaturePart[i]) {
091: return false;
092: }
093: }
094: return true;
095: }
096:
097: public int hashCode() {
098: return (int) (longPart ^ (longPart >>> 32));
099: }
100:
101: public String toString() {
102: if (!Debug4.prettyToStrings) {
103: return super .toString();
104: }
105:
106: String sig = "";
107: for (int i = 0; i < signaturePart.length; i++) {
108: sig += signaturePart[i] + " ";
109: }
110:
111: return "long " + longPart + " , signature " + sig;
112: }
113:
114: }
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