1 // Copyright (C) 2000 - 2009 Philip Aston
2 // All rights reserved.
3 //
4 // This file is part of The Grinder software distribution. Refer to
5 // the file LICENSE which is part of The Grinder distribution for
6 // licensing details. The Grinder distribution is available on the
7 // Internet at http://grinder.sourceforge.net/
8 //
9 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
10 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
11 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
12 // FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
13 // COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
14 // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15 // (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17 // HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20 // OF THE POSSIBILITY OF SUCH DAMAGE.
21
22 package net.grinder.statistics;
23
24 import java.util.Comparator;
25 import java.util.HashSet;
26 import java.util.Set;
27 import java.util.SortedSet;
28 import java.util.TreeSet;
29
30
31 /**
32 * An ordered collection of {@link ExpressionView}s.
33 *
34 * @author Philip Aston
35 * @see net.grinder.script.Statistics#registerDataLogExpression
36 * @see net.grinder.script.Statistics#registerSummaryExpression
37 */
38 public final class StatisticsView {
39
40 /**
41 * We define a <code>Comparator</code> for {@link ExpressionView}s
42 * rather than having the <code>ExpressionView</code> implement
43 * <code>Comparable</code> because our sort order is inconsistent with equals.
44 */
45 private static final Comparator<ExpressionView> s_expressionViewComparator =
46 new CreationOrderComparator();
47
48 /**
49 * We use this set to ensure that new views are unique. We can't
50 * do this with a SortedSet because our sort order is inconsistent
51 * with equals.
52 */
53 private final Set<ExpressionView> m_unique = new HashSet<ExpressionView>();
54
55 private final SortedSet<ExpressionView> m_columns;
56
57 /**
58 * Creates a new <code>StatisticsView</code> instance.
59 */
60 public StatisticsView() {
61 m_columns = new TreeSet<ExpressionView>(s_expressionViewComparator);
62 }
63
64 /**
65 * Add all the {@link ExpressionView}s in <code>other</code> to
66 * this <code>StatisticsView</code>.
67 *
68 * @param other Another <code>StatisticsView</code>.
69 */
70 public synchronized void add(StatisticsView other) {
71 for (ExpressionView expressionView : other.m_columns) {
72 add(expressionView);
73 }
74 }
75
76 /**
77 * Add the specified {@link ExpressionView} to this
78 * <code>StatisticsView</code>.
79 *
80 * @param statistic An {@link ExpressionView}.
81 */
82 public synchronized void add(ExpressionView statistic) {
83 if (!m_unique.contains(statistic)) {
84 m_unique.add(statistic);
85 m_columns.add(statistic);
86 }
87 }
88
89 /**
90 * Return our {@link ExpressionView}s as an array.
91 *
92 * @return The {@link ExpressionView}s.
93 */
94 public synchronized ExpressionView[] getExpressionViews() {
95 return m_columns.toArray(new ExpressionView[m_columns.size()]);
96 }
97
98 /**
99 * Package scope for unit tests.
100 */
101 static final class CreationOrderComparator
102 implements Comparator<ExpressionView> {
103
104 public int compare(ExpressionView viewA, ExpressionView viewB) {
105
106 if (viewA.getCreationOrder() < viewB.getCreationOrder()) {
107 return -1;
108 }
109 else if (viewA.getCreationOrder() > viewB.getCreationOrder()) {
110 return 1;
111 }
112 else {
113 // Should assert ? Same creation order => same instance.
114 return 0;
115 }
116 }
117 }
118 }