/*
* 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.io;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import org.apache.flink.annotation.PublicEvolving;
import org.apache.flink.api.common.ExecutionConfig;
import org.apache.flink.api.common.io.RichOutputFormat;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.api.java.typeutils.InputTypeConfigurable;
import org.apache.flink.configuration.Configuration;
/**
* An output format that writes record into collection
*/
@PublicEvolving
public class LocalCollectionOutputFormat<T> extends RichOutputFormat<T> implements InputTypeConfigurable {
private static final long serialVersionUID = 1L;
private static Map<Integer,Collection<?>> RESULT_HOLDER = new HashMap<Integer, Collection<?>>();
private transient ArrayList<T> taskResult;
private TypeSerializer<T> typeSerializer;
private int id;
public LocalCollectionOutputFormat(Collection<T> out) {
synchronized (RESULT_HOLDER) {
this.id = generateRandomId();
RESULT_HOLDER.put(this.id, out);
}
}
private int generateRandomId() {
int num = (int) (Math.random() * Integer.MAX_VALUE);
while (RESULT_HOLDER.containsKey(num)) {
num = (int) (Math.random() * Integer.MAX_VALUE);
}
return num;
}
@Override
public void configure(Configuration parameters) {}
@Override
public void open(int taskNumber, int numTasks) throws IOException {
this.taskResult = new ArrayList<T>();
}
@Override
public void writeRecord(T record) throws IOException {
T recordCopy = this.typeSerializer.createInstance();
recordCopy = this.typeSerializer.copy(record, recordCopy);
this.taskResult.add(recordCopy);
}
@Override
public void close() throws IOException {
synchronized (RESULT_HOLDER) {
@SuppressWarnings("unchecked")
Collection<T> result = (Collection<T>) RESULT_HOLDER.get(this.id);
result.addAll(this.taskResult);
}
}
@Override
@SuppressWarnings("unchecked")
public void setInputType(TypeInformation<?> type, ExecutionConfig executionConfig) {
this.typeSerializer = (TypeSerializer<T>)type.createSerializer(executionConfig);
}
}