/*
* 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 com.alibaba.jstorm.hdfs.trident.format;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import storm.trident.tuple.TridentTuple;
/**
* Basic <code>SequenceFormat</code> implementation that uses
* <code>LongWritable</code> for keys and <code>Text</code> for values.
*
*/
public class DefaultSequenceFormat implements SequenceFormat {
private transient LongWritable key;
private transient Text value;
private String keyField;
private String valueField;
public DefaultSequenceFormat(String keyField, String valueField){
this.keyField = keyField;
this.valueField = valueField;
}
@Override
public Class keyClass() {
return LongWritable.class;
}
@Override
public Class valueClass() {
return Text.class;
}
@Override
public Writable key(TridentTuple tuple) {
if(this.key == null){
this.key = new LongWritable();
}
this.key.set(tuple.getLongByField(this.keyField));
return this.key;
}
@Override
public Writable value(TridentTuple tuple) {
if(this.value == null){
this.value = new Text();
}
this.value.set(tuple.getStringByField(this.valueField));
return this.value;
}
}