001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.monitoring;
019
020import static org.junit.Assert.assertFalse;
021import static org.junit.Assert.assertTrue;
022
023import java.io.PrintWriter;
024import java.io.StringWriter;
025import org.apache.hadoop.hbase.HBaseClassTestRule;
026import org.apache.hadoop.hbase.testclassification.MiscTests;
027import org.apache.hadoop.hbase.testclassification.SmallTests;
028import org.junit.ClassRule;
029import org.junit.Test;
030import org.junit.experimental.categories.Category;
031
032/**
033 * Test case for the MemoryBoundedLogMessageBuffer utility.
034 * Ensures that it uses no more memory than it's supposed to,
035 * and that it properly deals with multibyte encodings.
036 */
037@Category({MiscTests.class, SmallTests.class})
038public class TestMemoryBoundedLogMessageBuffer {
039
040  @ClassRule
041  public static final HBaseClassTestRule CLASS_RULE =
042      HBaseClassTestRule.forClass(TestMemoryBoundedLogMessageBuffer.class);
043
044  private static final long TEN_KB = 10 * 1024;
045  private static final String JP_TEXT = "こんにちは";
046
047  @Test
048  public void testBuffer() {
049    MemoryBoundedLogMessageBuffer buf =
050      new MemoryBoundedLogMessageBuffer(TEN_KB);
051
052    for (int i = 0; i < 1000; i++) {
053      buf.add("hello " + i);
054    }
055    assertTrue("Usage too big: " + buf.estimateHeapUsage(),
056        buf.estimateHeapUsage() < TEN_KB);
057    assertTrue("Too many retained: " + buf.getMessages().size(),
058        buf.getMessages().size() < 100);
059    StringWriter sw = new StringWriter();
060    buf.dumpTo(new PrintWriter(sw));
061    String dump = sw.toString();
062    String eol = System.getProperty("line.separator");
063    assertFalse("The early log messages should be evicted",
064        dump.contains("hello 1" + eol));
065    assertTrue("The late log messages should be retained",
066        dump.contains("hello 999" + eol));
067  }
068
069  @Test
070  public void testNonAsciiEncoding() {
071    MemoryBoundedLogMessageBuffer buf =
072      new MemoryBoundedLogMessageBuffer(TEN_KB);
073
074    buf.add(JP_TEXT);
075    StringWriter sw = new StringWriter();
076    buf.dumpTo(new PrintWriter(sw));
077    String dump = sw.toString();
078    assertTrue(dump.contains(JP_TEXT));
079  }
080
081}
082