com.asakusafw.lang.compiler.mapreduce.testing.mock.WritableOutputFormat.java Source code

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Here is the source code for com.asakusafw.lang.compiler.mapreduce.testing.mock.WritableOutputFormat.java

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/**
 * Copyright 2011-2017 Asakusa Framework Team.
 *
 * Licensed 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.asakusafw.lang.compiler.mapreduce.testing.mock;

import java.io.IOException;

import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

import com.asakusafw.runtime.io.ModelOutput;

/**
 * An output format with {@link WritableModelOutput}.
 * @param <T> data model type
 */
public class WritableOutputFormat<T extends Writable> extends FileOutputFormat<NullWritable, T> {

    @Override
    public RecordWriter<NullWritable, T> getRecordWriter(TaskAttemptContext context)
            throws IOException, InterruptedException {
        Path path = getDefaultWorkFile(context, null);
        FileSystem fs = path.getFileSystem(context.getConfiguration());
        return new Writer<>(new WritableModelOutput<T>(fs.create(path, true)));
    }

    private static final class Writer<T extends Writable> extends RecordWriter<NullWritable, T> {

        private final ModelOutput<T> output;

        Writer(ModelOutput<T> output) {
            this.output = output;
        }

        @Override
        public void write(NullWritable key, T value) throws IOException, InterruptedException {
            output.write(value);
        }

        @Override
        public void close(TaskAttemptContext context) throws IOException, InterruptedException {
            output.close();
        }
    }
}