HadoopOutputFormatCommonBase.java

/*
 * 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.hadoop.common;

import org.apache.flink.annotation.Internal;
import org.apache.flink.api.common.io.RichOutputFormat;
import org.apache.hadoop.security.Credentials;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

/**
 * A common base for both "mapred" and "mapreduce" Hadoop output formats.
 *
 * The base is taking care of handling (serializing) security credentials.
 */
@Internal
public abstract class HadoopOutputFormatCommonBase<T> extends RichOutputFormat<T> {
	protected transient Credentials credentials;

	protected HadoopOutputFormatCommonBase(Credentials creds) {
		this.credentials = creds;
	}

	protected void write(ObjectOutputStream out) throws IOException {
		this.credentials.write(out);
	}

	public void read(ObjectInputStream in) throws IOException {
		this.credentials = new Credentials();
		credentials.readFields(in);
	}
}