1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.configuration2.builder;
18
19 import static org.junit.jupiter.api.Assertions.assertEquals;
20 import static org.junit.jupiter.api.Assertions.assertFalse;
21 import static org.junit.jupiter.api.Assertions.assertTrue;
22
23 import java.util.Iterator;
24 import java.util.LinkedList;
25 import java.util.List;
26
27 import org.apache.commons.configuration2.event.EventListener;
28 import org.apache.commons.configuration2.event.EventType;
29
30 /**
31 * A test implementation of an event listener for configuration builders. This class is used by some unit tests. It
32 * collects the events received by the listener and provides some methods for querying them.
33 */
34 public class BuilderEventListenerImpl implements EventListener<ConfigurationBuilderEvent> {
35 /** A list with the received events. */
36 private final List<ConfigurationBuilderEvent> events = new LinkedList<>();
37
38 /** An iterator for inspecting the received events. */
39 private Iterator<ConfigurationBuilderEvent> iterator;
40
41 /**
42 * Checks that no further events have been received by this listener.
43 */
44 public void assertNoMoreEvents() {
45 assertFalse(initIterator().hasNext());
46 }
47
48 /**
49 * Ensures that the iterator for received events has been initialized.
50 *
51 * @return the iterator to be used
52 */
53 private Iterator<ConfigurationBuilderEvent> initIterator() {
54 if (iterator == null) {
55 iterator = events.iterator();
56 }
57 return iterator;
58 }
59
60 /**
61 * Checks whether the next received event is of the specified event type and returns it. Causes the test to fail if
62 * there are no more events or the next event is of a different event type.
63 *
64 * @param eventType the expected event type
65 * @param <T> the type of the received event
66 * @return the next received event
67 */
68 public <T extends ConfigurationBuilderEvent> T nextEvent(final EventType<T> eventType) {
69 final Iterator<ConfigurationBuilderEvent> it = initIterator();
70 assertTrue(it.hasNext());
71 final ConfigurationBuilderEvent nextEvent = it.next();
72 assertEquals(eventType, nextEvent.getEventType());
73 // Safe cast because of the comparison of the event type
74 @SuppressWarnings("unchecked")
75 final T resultEvent = (T) nextEvent;
76 return resultEvent;
77 }
78
79 /**
80 * {@inheritDoc} This implementation just records the event.
81 */
82 @Override
83 public void onEvent(final ConfigurationBuilderEvent event) {
84 events.add(event);
85 }
86 }