1 /**
2 * Copyright (c) 2011, University of Konstanz, Distributed Systems Group
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of the University of Konstanz nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
20 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 package org.treetank.service.xml.diff;
29
30 import java.util.HashSet;
31 import java.util.Set;
32
33 import org.treetank.api.INodeReadTrx;
34 import org.treetank.exception.TTException;
35 import org.treetank.node.interfaces.IStructNode;
36 import org.treetank.service.xml.diff.DiffFactory.EDiff;
37
38 /**
39 * Implements {@link IDiffObservable}, which can be used for all classes, which
40 * implement the {@link IDiff} interface.
41 *
42 * @author Johannes Lichtenberger, University of Konstanz
43 *
44 */
45 abstract class AbsDiffObservable implements IDiffObservable {
46
47 /** {@link IReadTransaction} on new revision. */
48 transient INodeReadTrx mNewRtx;
49
50 /** {@link IReadTransaction} on old revision. */
51 transient INodeReadTrx mOldRtx;
52
53 /**
54 * {@link Set} of observers, which want to be notified of the encountered
55 * differences.
56 */
57 private final Set<IDiffObserver> mDiffObservers;
58
59 /**
60 * Default constructor.
61 */
62 AbsDiffObservable() {
63 mDiffObservers = new HashSet<IDiffObserver>();
64 }
65
66 /** {@inheritDoc} */
67 @Override
68 public final void fireDiff(final EDiff paramDiff, final IStructNode paramNewNode,
69 final IStructNode paramOldNode, final DiffDepth paramDepth) {
70 for (final IDiffObserver observer : mDiffObservers) {
71 observer.diffListener(paramDiff, paramNewNode, paramOldNode, paramDepth);
72 }
73 }
74
75 /**
76 * {@inheritDoc}
77 *
78 */
79 @Override
80 public final void done() throws TTException {
81 mNewRtx.close();
82 mOldRtx.close();
83
84 for (final IDiffObserver observer : mDiffObservers) {
85 observer.diffDone();
86 }
87 }
88
89 /** {@inheritDoc} */
90 @Override
91 public final void addObserver(final IDiffObserver paramObserver) {
92 mDiffObservers.add(paramObserver);
93 }
94
95 /** {@inheritDoc} */
96 @Override
97 public final void removeObserver(final IDiffObserver paramObserver) {
98 mDiffObservers.remove(paramObserver);
99 }
100 }