TestCompressionTest.java

/*
 * Copyright 2010 The Apache Software Foundation
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hadoop.hbase.util;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.io.hfile.Compression;
import org.apache.hadoop.io.DataOutputBuffer;
import org.apache.hadoop.io.compress.CompressionCodec;
import org.apache.hadoop.io.compress.CompressionOutputStream;
import org.apache.hadoop.util.NativeCodeLoader;
import org.apache.hadoop.util.ReflectionUtils;
import org.junit.Test;

import java.io.BufferedOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;

import static org.junit.Assert.*;

public class TestCompressionTest {

  @Test
  public void testTestCompression() {

    // This test will fail if you run the tests with LZO compression available.
    try {
      CompressionTest.testCompression(Compression.Algorithm.LZO);
      fail(); // always throws
    } catch (IOException e) {
      // there should be a 'cause'.
      assertNotNull(e.getCause());
    }

    // this is testing the caching of the test results.
    try {
      CompressionTest.testCompression(Compression.Algorithm.LZO);
      fail(); // always throws
    } catch (IOException e) {
      // there should be NO cause because it's a direct exception not wrapped
      assertNull(e.getCause());
    }


    assertFalse(CompressionTest.testCompression("LZO"));
    assertTrue(CompressionTest.testCompression("NONE"));
    assertTrue(CompressionTest.testCompression("GZ"));

    if (isCompressionAvailable("org.apache.hadoop.io.compress.SnappyCodec")) {
      if (NativeCodeLoader.isNativeCodeLoaded()) {
        try {
          System.loadLibrary("snappy");

          try {
            Configuration conf = new Configuration();
            CompressionCodec codec = (CompressionCodec)
              ReflectionUtils.newInstance(
                conf.getClassByName("org.apache.hadoop.io.compress.SnappyCodec"), conf);

            DataOutputBuffer compressedDataBuffer = new DataOutputBuffer();
            CompressionOutputStream deflateFilter =
              codec.createOutputStream(compressedDataBuffer);

            byte[] data = new byte[1024];
            DataOutputStream deflateOut = new DataOutputStream(
              new BufferedOutputStream(deflateFilter));
            deflateOut.write(data, 0, data.length);
            deflateOut.flush();
            deflateFilter.finish();

            // Snappy Codec class, Snappy nativelib and Hadoop nativelib with 
            // Snappy JNIs are present
            assertTrue(CompressionTest.testCompression("SNAPPY"));
          }
          catch (UnsatisfiedLinkError ex) {
            // Hadoop nativelib does not have Snappy JNIs
            
            // cannot assert the codec here because the current logic of 
            // CompressionTest checks only classloading, not the codec
            // usage.
          }
          catch (Exception ex) {
          }
        }
        catch (UnsatisfiedLinkError ex) {
          // Snappy nativelib is not available
          assertFalse(CompressionTest.testCompression("SNAPPY"));
        }
      }
      else {
        // Hadoop nativelib is not available
        assertFalse(CompressionTest.testCompression("SNAPPY"));
      }
    }
    else {
      // Snappy Codec class is not available
      assertFalse(CompressionTest.testCompression("SNAPPY"));
    }
  }

  private boolean isCompressionAvailable(String codecClassName) {
    try {
      Thread.currentThread().getContextClassLoader().loadClass(codecClassName);
      return true;
    }
    catch (Exception ex) {
      return false;
    }
  }

}