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. Ensures that it uses no more memory than
034 * it's supposed to, and that it properly deals with multibyte encodings.
035 */
036@Category({ MiscTests.class, SmallTests.class })
037public class TestMemoryBoundedLogMessageBuffer {
038
039  @ClassRule
040  public static final HBaseClassTestRule CLASS_RULE =
041    HBaseClassTestRule.forClass(TestMemoryBoundedLogMessageBuffer.class);
042
043  private static final long TEN_KB = 10 * 1024;
044  private static final String JP_TEXT = "こんにちは";
045
046  @Test
047  public void testBuffer() {
048    MemoryBoundedLogMessageBuffer buf = new MemoryBoundedLogMessageBuffer(TEN_KB);
049
050    for (int i = 0; i < 1000; i++) {
051      buf.add("hello " + i);
052    }
053    assertTrue("Usage too big: " + buf.estimateHeapUsage(), buf.estimateHeapUsage() < TEN_KB);
054    assertTrue("Too many retained: " + buf.getMessages().size(), buf.getMessages().size() < 100);
055    StringWriter sw = new StringWriter();
056    buf.dumpTo(new PrintWriter(sw));
057    String dump = sw.toString();
058    String eol = System.getProperty("line.separator");
059    assertFalse("The early log messages should be evicted", dump.contains("hello 1" + eol));
060    assertTrue("The late log messages should be retained", dump.contains("hello 999" + eol));
061  }
062
063  @Test
064  public void testNonAsciiEncoding() {
065    MemoryBoundedLogMessageBuffer buf = new MemoryBoundedLogMessageBuffer(TEN_KB);
066
067    buf.add(JP_TEXT);
068    StringWriter sw = new StringWriter();
069    buf.dumpTo(new PrintWriter(sw));
070    String dump = sw.toString();
071    assertTrue(dump.contains(JP_TEXT));
072  }
073
074}