diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.java
index b2d3dcc5770..b18e70f7623 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.java
@@ -175,7 +175,7 @@ public class ProtobufLogReader extends ReaderBase {
@Override
protected void initAfterCompression() throws IOException {
- WALCellCodec codec = new WALCellCodec(this.compressionContext);
+ WALCellCodec codec = WALCellCodec.create(this.conf, this.compressionContext);
this.cellDecoder = codec.getDecoder(this.inputStream);
if (this.hasCompression) {
this.byteStringUncompressor = codec.getByteStringUncompressor();
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java
index a5fca766d17..c5521df5f1a 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java
@@ -80,7 +80,7 @@ public class ProtobufLogWriter implements HLog.Writer {
output.write(ProtobufLogReader.PB_WAL_MAGIC);
WALHeader.newBuilder().setHasCompression(doCompress).build().writeDelimitedTo(output);
- WALCellCodec codec = new WALCellCodec(this.compressionContext);
+ WALCellCodec codec = WALCellCodec.create(conf, this.compressionContext);
this.cellEncoder = codec.getEncoder(this.output);
if (doCompress) {
this.compressor = codec.getByteStringCompressor();
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java
index 245abba2ddc..4491a92519b 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java
@@ -22,6 +22,7 @@ import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
+import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.codec.BaseDecoder;
@@ -29,6 +30,7 @@ import org.apache.hadoop.hbase.codec.BaseEncoder;
import org.apache.hadoop.hbase.codec.Codec;
import org.apache.hadoop.hbase.codec.KeyValueCodec;
import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.util.ReflectionUtils;
import com.google.common.base.Preconditions;
import com.google.protobuf.ByteString;
@@ -39,6 +41,9 @@ import com.google.protobuf.ByteString;
* This is a pure coincidence... they are independent and don't have to be compatible.
*/
public class WALCellCodec implements Codec {
+ /** Configuration key for the class to use when encoding cells in the WAL */
+ public static final String WAL_CELL_CODEC_CLASS_KEY = "hbase.regionserver.wal.codec";
+
private final CompressionContext compression;
private final ByteStringUncompressor statelessUncompressor = new ByteStringUncompressor() {
@Override
@@ -47,10 +52,33 @@ public class WALCellCodec implements Codec {
}
};
- public WALCellCodec(CompressionContext compression) {
+ /**
+ * Default constructor - all subclasses must implement a constructor with this signature
+ * if they are to be dynamically loaded from the {@link Configuration}.
+ * @param conf configuration to configure this
+ * @param compression compression the codec should support, can be null to indicate no
+ * compression
+ */
+ public WALCellCodec(Configuration conf, CompressionContext compression) {
this.compression = compression;
}
+ /**
+ * Create and setup a {@link WALCellCodec} from the {@link Configuration} and CompressionContext,
+ * if they have been specified. Fully prepares the codec for use.
+ * @param conf {@link Configuration} to read for the user-specified codec. If none is specified,
+ * uses a {@link WALCellCodec}.
+ * @param compression compression the codec should use
+ * @return a {@link WALCellCodec} ready for use.
+ * @throws UnsupportedOperationException if the codec cannot be instantiated
+ */
+ public static WALCellCodec create(Configuration conf, CompressionContext compression)
+ throws UnsupportedOperationException {
+ String className = conf.get(WAL_CELL_CODEC_CLASS_KEY, WALCellCodec.class.getName());
+ return ReflectionUtils.instantiateWithCustomCtor(className, new Class[] { Configuration.class,
+ CompressionContext.class }, new Object[] { conf, compression });
+ }
+
public interface ByteStringCompressor {
ByteString compress(byte[] data, Dictionary dict) throws IOException;
}
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestCustomWALCellCodec.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestCustomWALCellCodec.java
new file mode 100644
index 00000000000..b992aca2671
--- /dev/null
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestCustomWALCellCodec.java
@@ -0,0 +1,62 @@
+/**
+ * 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.regionserver.wal;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.SmallTests;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+
+/**
+ * Test that we can create, load, setup our own custom codec
+ */
+@Category(SmallTests.class)
+public class TestCustomWALCellCodec {
+
+ public static class CustomWALCellCodec extends WALCellCodec {
+ public Configuration conf;
+ public CompressionContext context;
+
+ public CustomWALCellCodec(Configuration conf, CompressionContext compression) {
+ super(conf, compression);
+ this.conf = conf;
+ this.context = compression;
+ }
+ }
+
+ /**
+ * Test that a custom {@link WALCellCodec} will be completely setup when it is instantiated via
+ * {@link WALCellCodec}
+ * @throws Exception on failure
+ */
+ @Test
+ public void testCreatePreparesCodec() throws Exception {
+ Configuration conf = new Configuration(false);
+ conf.setClass(WALCellCodec.WAL_CELL_CODEC_CLASS_KEY, CustomWALCellCodec.class,
+ WALCellCodec.class);
+ CustomWALCellCodec codec = (CustomWALCellCodec) WALCellCodec.create(conf, null);
+ assertEquals("Custom codec didn't get initialized with the right configuration!", conf,
+ codec.conf);
+ assertEquals("Custom codec didn't get initialized with the right compression context!", null,
+ codec.context);
+ }
+}
\ No newline at end of file