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.log4j;
18
19 import junit.framework.Assert;
20
21 import org.apache.log4j.Level;
22 import org.apache.log4j.Logger;
23 import org.apache.log4j.VectorAppender;
24 import org.apache.log4j.spi.LoggingEvent;
25
26 import java.util.Vector;
27
28
29 /**
30 * Helper class to set up and capture log messages.
31 */
32 public class LogCapture {
33 /**
34 * Appender.
35 */
36 private final VectorAppender appender;
37
38 /**
39 * Expected level.
40 */
41 private final Level level;
42
43 /**
44 * Creates new instance of LogCapture.
45 *
46 */
47 public LogCapture(final Level level) {
48 this.level = level;
49
50 Logger root = Logger.getRootLogger();
51 appender = new VectorAppender();
52 root.addAppender(appender);
53 }
54
55 /**
56 * Get message.
57 * @return rendered message, null if no logging event captured.
58 */
59 public String getMessage() {
60 Vector vector = appender.getVector();
61 String msg = null;
62
63 switch (vector.size()) {
64 case 0:
65 break;
66
67 case 1:
68
69 LoggingEvent event = (LoggingEvent) vector.elementAt(0);
70 Assert.assertNotNull(event);
71 Assert.assertEquals(level, event.getLevel());
72 msg = event.getRenderedMessage();
73
74 break;
75
76 default:
77 Assert.fail("More than one request captured");
78 }
79
80 return msg;
81 }
82 }