1/*
2 * Copyright (C) 2008 Google Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.google.common.testing;
18
19import junit.framework.TestCase;
20
21import java.util.logging.Level;
22import java.util.logging.LogRecord;
23import java.util.logging.Logger;
24
25/**
26 * Unit test for {@link TestLogHandler}.
27 *
28 * @author kevinb
29 */
30public class TestLogHandlerTest extends TestCase {
31
32  private TestLogHandler handler;
33  private TearDownStack stack = new TearDownStack();
34
35  @Override protected void setUp() throws Exception {
36    super.setUp();
37
38    handler = new TestLogHandler();
39
40    // You could also apply it higher up the Logger hierarchy than this
41    ExampleClassUnderTest.logger.addHandler(handler);
42
43    ExampleClassUnderTest.logger.setUseParentHandlers(false); // optional
44
45    stack.addTearDown(new TearDown() {
46      @Override
47      public void tearDown() throws Exception {
48        ExampleClassUnderTest.logger.setUseParentHandlers(true);
49        ExampleClassUnderTest.logger.removeHandler(handler);
50      }
51    });
52  }
53
54  public void test() throws Exception {
55    assertTrue(handler.getStoredLogRecords().isEmpty());
56    ExampleClassUnderTest.foo();
57    LogRecord record = handler.getStoredLogRecords().iterator().next();
58    assertEquals(Level.INFO, record.getLevel());
59    assertEquals("message", record.getMessage());
60    assertSame(EXCEPTION, record.getThrown());
61  }
62
63  public void testConcurrentModification() throws Exception {
64    // Tests for the absence of a bug where logging while iterating over the
65    // stored log records causes a ConcurrentModificationException
66    assertTrue(handler.getStoredLogRecords().isEmpty());
67    ExampleClassUnderTest.foo();
68    ExampleClassUnderTest.foo();
69    for (LogRecord record : handler.getStoredLogRecords()) {
70      ExampleClassUnderTest.foo();
71    }
72  }
73
74  @Override public final void runBare() throws Throwable {
75    try {
76      setUp();
77      runTest();
78    } finally {
79      tearDown();
80    }
81  }
82
83  @Override protected void tearDown() {
84    stack.runTearDown();
85  }
86
87  static final Exception EXCEPTION = new Exception();
88
89  static class ExampleClassUnderTest {
90    static final Logger logger
91        = Logger.getLogger(ExampleClassUnderTest.class.getName());
92
93    static void foo() {
94      logger.log(Level.INFO,  "message", EXCEPTION);
95    }
96  }
97}
98