HBASE-15881 Allow BZIP2 compression.

hbase-common/src/main/java/org/apache/hadoop/hbase/io/compress/Compression.java

@@ -235,7 +235,34 @@ public final class Compression {
           throw new RuntimeException(e);
         }
       }
-  };
+    },
+    BZIP2("bzip2") {
+      // Use base type to avoid compile-time dependencies.
+      private volatile transient CompressionCodec bzipCodec;
+      private transient Object lock = new Object();
+
+      @Override
+      CompressionCodec getCodec(Configuration conf) {
+        if (bzipCodec == null) {
+          synchronized (lock) {
+            if (bzipCodec == null) {
+              bzipCodec = buildCodec(conf);
+            }
+          }
+        }
+        return bzipCodec;
+      }
+
+      private CompressionCodec buildCodec(Configuration conf) {
+        try {
+          Class<?> externalCodec =
+              getClassLoaderForCodec().loadClass("org.apache.hadoop.io.compress.BZip2Codec");
+          return (CompressionCodec) ReflectionUtils.newInstance(externalCodec, conf);
+        } catch (ClassNotFoundException e) {
+          throw new RuntimeException(e);
+        }
+      }
+    };
 
     private final Configuration conf;
     private final String compressName;

hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestCompressionTest.java

@@ -75,12 +75,14 @@ public class TestCompressionTest {
       nativeCodecTest("LZO", "lzo2", "com.hadoop.compression.lzo.LzoCodec");
       nativeCodecTest("LZ4", null, "org.apache.hadoop.io.compress.Lz4Codec");
       nativeCodecTest("SNAPPY", "snappy", "org.apache.hadoop.io.compress.SnappyCodec");
+      nativeCodecTest("BZIP2", "bzip2", "org.apache.hadoop.io.compress.BZip2Codec");
     } else {
       // Hadoop nativelib is not available
       LOG.debug("Native code not loaded");
       assertFalse(CompressionTest.testCompression("LZO"));
       assertFalse(CompressionTest.testCompression("LZ4"));
       assertFalse(CompressionTest.testCompression("SNAPPY"));
+      assertFalse(CompressionTest.testCompression("BZIP2"));
     }
   }