1 /*
2 * Copyright (c) 2005 Regents of the University of California (Regents). Created
3 * by TELS, Graduate School of Education, University of California at Berkeley.
4 *
5 * This software is distributed under the GNU Lesser General Public License, v2.
6 *
7 * Permission is hereby granted, without written agreement and without license
8 * or royalty fees, to use, copy, modify, and distribute this software and its
9 * documentation for any purpose, provided that the above copyright notice and
10 * the following two paragraphs appear in all copies of this software.
11 *
12 * REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
13 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
14 * PURPOSE. THE SOFTWAREAND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
15 * HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
16 * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
17 *
18 * IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
19 * SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,
20 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
21 * REGENTS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
22 */
23 package net.sf.sail.core.entity;
24
25 import java.util.HashSet;
26
27 /**
28 * Extends HashSet to add some handy methods for Agents
29 *
30 * @author turadg
31 *
32 */
33 public class AgentSet extends HashSet<IAgent> {
34
35 private static final long serialVersionUID = 8185517197325172183L;
36
37 /**
38 * Assumes there is only one agent in the set
39 * @throws MismatchedAgentSetSizeException
40 */
41 public IAgent getSingle() throws MismatchedAgentSetSizeException {
42 // TODO make a checked exception for this
43 if (size() > 1)
44 throw new MismatchedAgentSetSizeException(1, size());
45 if (isEmpty())
46 throw new MismatchedAgentSetSizeException(1, 0);
47 // otherwise, length is 1
48 return iterator().next();
49 }
50
51 public AgentSet select(Role role) {
52 AgentSet subset = new AgentSet();
53 for (IAgent agent : this) {
54 if (agent.getRole().equals(role))
55 subset.add(agent);
56 }
57 return subset;
58 }
59 }