/**
* 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 io.dstream.tez.io;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.nio.ByteBuffer;
import org.apache.commons.io.output.ByteArrayOutputStream;
/**
*
*/
@SuppressWarnings("unchecked")
public abstract class TypeAwareWritable<T> implements NewWritable<T> {
protected T value;
private byte valueType = NULL;
private final ValueEncoder valueEncoder = new ValueEncoder();
/**
*
*/
@Override
public void setValue(T value) {
this.value = value;
this.determineValueType(value);
this.valueType = this.valueEncoder.valueType;
}
/**
*
*/
@Override
public T getValue() {
return this.value;
}
/**
*
*/
@Override
public int hashCode() {
int hashCode = 0;
if (this.value != null){
hashCode = this.value.hashCode();
}
return hashCode;
}
/**
*
*/
@Override
public void write(DataOutput out) throws IOException {
out.writeByte(this.valueType);
if (this.valueType != NULL){
try {
out.write(this.valueEncoder.valueBytes);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
/**
*
*/
@Override
public void readFields(DataInput in) throws IOException {
this.valueType = in.readByte();
switch (this.valueType) {
case INTEGER:
this.value = (T) Integer.valueOf(in.readInt());
break;
case LONG:
this.value = (T) Long.valueOf(in.readLong());
break;
case NULL:
this.value = null;
break;
case OBJECT:
try {
ObjectInputStream ois = new ObjectInputStream((DataInputStream) in);
T value = (T) ois.readObject();
this.value = value;
} catch (Exception e) {
throw new IllegalStateException(
"Failed to deserialize value", e);
}
break;
default:
throw new IllegalStateException(
"Unsupported or unrecognized value type: "
+ this.valueType);
}
}
/**
*
*/
@Override
public String toString(){
if (this.value == null){
return null;
} else {
return this.value.toString();
}
}
/**
* NOTE: The below code is temporary and both conversion and ser/deser will be exposed through externally
* configurable framework!
*
* @param value
* @return
*/
private void determineValueType(Object value){
if (value instanceof Integer){
this.valueEncoder.valueType = INTEGER;
this.valueEncoder.valueBytes = ByteBuffer.allocate(4).putInt((Integer)value).array();
}
else if (value instanceof Long) {
this.valueEncoder.valueType = LONG;
this.valueEncoder.valueBytes = ByteBuffer.allocate(8).putLong((Long)value).array();
}
else if (value == null){
this.valueEncoder.valueType = NULL;
}
else {
ObjectOutputStream oos = null;
try {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
oos = new ObjectOutputStream(bos);
oos.writeObject(value);
this.valueEncoder.valueType = OBJECT;
this.valueEncoder.valueBytes = bos.toByteArray();
} catch (Exception e) {
throw new IllegalStateException("Failed to serialize value: " + value, e);
} finally {
try {
if (oos != null){
oos.close();
}
} catch (Exception e2) {/*ignore*/}
}
}
}
private final static byte INTEGER = -128;
private final static byte STRING = -127;
private final static byte LONG = -126;
private final static byte OBJECT = -125;
private final static byte NULL = -124;
/**
*/
private class ValueEncoder {
private byte valueType;
private byte[] valueBytes;
}
}