SessionInfoStore.java revision d05ad7d4bc65e91b6c6efb45687f7a850d07f02a 
1/*******************************************************************************
2 * Copyright (c) 2009, 2011 Mountainminds GmbH & Co. KG and Contributors
3 * All rights reserved. This program and the accompanying materials
4 * are made available under the terms of the Eclipse Public License v1.0
5 * which accompanies this distribution, and is available at
6 * http://www.eclipse.org/legal/epl-v10.html
7 *
8 * Contributors:
9 *    Marc R. Hoffmann - initial API and implementation
10 *
11 *******************************************************************************/
12package org.jacoco.core.data;
13
14import static java.lang.Math.max;
15import static java.lang.Math.min;
16
17import java.util.ArrayList;
18import java.util.Collections;
19import java.util.List;
20
21/**
22 * Container to collect and merge session {@link SessionInfo} objects. A
23 * instance of this class is not thread safe.
24 *
25 * @author Marc R. Hoffmann
26 * @version $qualified.bundle.version$
27 */
28public class SessionInfoStore implements ISessionInfoVisitor {
29
30	private final List<SessionInfo> infos = new ArrayList<SessionInfo>();
31
32	/**
33	 * Tests whether the store is empty.
34	 *
35	 * @return <code>true</code> if the store is empty
36	 */
37	public boolean isEmpty() {
38		return infos.isEmpty();
39	}
40
41	/**
42	 * Returns all {@link SessionInfo} objects currently contained in the store.
43	 * The info objects are ordered by its natural ordering (i.e. by the dump
44	 * time stamp).
45	 *
46	 * @return list of stored {@link SessionInfo} objects
47	 */
48	public List<SessionInfo> getInfos() {
49		final List<SessionInfo> copy = new ArrayList<SessionInfo>(infos);
50		Collections.sort(copy);
51		return copy;
52	}
53
54	/**
55	 * Returns a new session info with the given id that contains a merged
56	 * version from all contained version. The start timestamp is the minimum of
57	 * all contained sessions, the dump timestamp the maximum of all contained
58	 * sessions. If no session is currently contained both timestamps are set to
59	 * <code>0</code>.
60	 *
61	 * @param id
62	 *            identifier for the merged session info
63	 * @return new {@link SessionInfo} object
64	 *
65	 */
66	public SessionInfo getMerged(final String id) {
67		if (infos.isEmpty()) {
68			return new SessionInfo(id, 0, 0);
69		}
70		long start = Long.MAX_VALUE;
71		long dump = Long.MIN_VALUE;
72		for (final SessionInfo i : infos) {
73			start = min(start, i.getStartTimeStamp());
74			dump = max(dump, i.getDumpTimeStamp());
75		}
76		return new SessionInfo(id, start, dump);
77	}
78
79	/**
80	 * Writes all contained {@link SessionInfo} objects into the given visitor.
81	 * The info objects are emitted in chronological order by dump timestamp.
82	 *
83	 * @param visitor
84	 *            visitor to emit {@link SessionInfo} objects to
85	 */
86	public void accept(final ISessionInfoVisitor visitor) {
87		for (final SessionInfo i : getInfos()) {
88			visitor.visitSessionInfo(i);
89		}
90	}
91
92	// === ISessionInfoVisitor ===
93
94	public void visitSessionInfo(final SessionInfo info) {
95		infos.add(info);
96	}
97
98}
99