/*
* 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.flink.api.java.typeutils.runtime;
import java.io.IOException;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.core.memory.DataInputView;
import org.apache.flink.core.memory.DataOutputView;
import org.apache.flink.types.Value;
import org.apache.flink.util.InstantiationUtil;
import com.esotericsoftware.kryo.Kryo;
/**
* Serializer for {@link Value} types. Uses the value's serialization methods, and uses
* Kryo for deep object copies.
*
* @param <T> The type serialized.
*/
public class ValueSerializer<T extends Value> extends TypeSerializer<T> {
private static final long serialVersionUID = 1L;
private final Class<T> type;
private transient Kryo kryo;
private transient T copyInstance;
// --------------------------------------------------------------------------------------------
public ValueSerializer(Class<T> type) {
if (type == null) {
throw new NullPointerException();
}
this.type = type;
}
// --------------------------------------------------------------------------------------------
@Override
public boolean isImmutableType() {
return false;
}
@Override
public boolean isStateful() {
return true;
}
@Override
public T createInstance() {
return InstantiationUtil.instantiate(this.type);
}
@Override
public T copy(T from) {
checkKryoInitialized();
return this.kryo.copy(from);
}
@Override
public T copy(T from, T reuse) {
checkKryoInitialized();
return this.kryo.copy(from);
}
@Override
public int getLength() {
return -1;
}
@Override
public void serialize(T value, DataOutputView target) throws IOException {
value.write(target);
}
@Override
public T deserialize(DataInputView source) throws IOException {
return deserialize(createInstance(), source);
}
@Override
public T deserialize(T reuse, DataInputView source) throws IOException {
reuse.read(source);
return reuse;
}
@Override
public void copy(DataInputView source, DataOutputView target) throws IOException {
if (this.copyInstance == null) {
this.copyInstance = InstantiationUtil.instantiate(type);
}
this.copyInstance.read(source);
this.copyInstance.write(target);
}
private void checkKryoInitialized() {
if (this.kryo == null) {
this.kryo = new Kryo();
this.kryo.setAsmEnabled(true);
this.kryo.register(type);
}
}
// --------------------------------------------------------------------------------------------
@Override
public int hashCode() {
return this.type.hashCode() + 17;
}
@Override
public boolean equals(Object obj) {
if (obj.getClass() == ValueSerializer.class) {
ValueSerializer<?> other = (ValueSerializer<?>) obj;
return this.type == other.type;
} else {
return false;
}
}
}