/*
* Copyright 2011 LinkedIn, Inc
*
* Licensed 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 voldemort.serialization.avro;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import org.apache.avro.Schema;
import org.apache.avro.generic.GenericDatumReader;
import org.apache.avro.generic.GenericDatumWriter;
import org.apache.avro.io.BinaryEncoder;
import org.apache.avro.io.Decoder;
import org.apache.avro.io.DecoderFactory;
import org.apache.avro.io.Encoder;
import voldemort.serialization.SerializationException;
import voldemort.serialization.SerializationUtils;
import voldemort.serialization.Serializer;
/**
* Avro serializer that uses the generic representation for Avro data. This
* representation is best for applications which deal with dynamic data, whose
* schemas are not known until runtime.
*
*/
public class AvroGenericSerializer implements Serializer<Object> {
private final Schema typeDef;
/**
* Constructor accepting the schema definition as a JSON string.
*
* @param schema a serialized JSON object representing a Avro schema.
*/
public AvroGenericSerializer(String schema) {
typeDef = Schema.parse(schema);
}
public byte[] toBytes(Object object) {
ByteArrayOutputStream output = new ByteArrayOutputStream();
Encoder encoder = new BinaryEncoder(output);
GenericDatumWriter<Object> datumWriter = null;
try {
datumWriter = new GenericDatumWriter<Object>(typeDef);
datumWriter.write(object, encoder);
encoder.flush();
} catch(IOException e) {
throw new SerializationException(e);
} finally {
SerializationUtils.close(output);
}
return output.toByteArray();
}
public Object toObject(byte[] bytes) {
Decoder decoder = DecoderFactory.defaultFactory().createBinaryDecoder(bytes, null);
GenericDatumReader<Object> reader = null;
try {
reader = new GenericDatumReader<Object>(typeDef);
return reader.read(null, decoder);
} catch(IOException e) {
throw new SerializationException(e);
}
}
}