Java tutorial
/** * Licensed to Cloudera, Inc. under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. Cloudera, Inc. 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.cloudera.sqoop.mapreduce; import java.io.IOException; import org.apache.avro.Schema; import org.apache.avro.file.DataFileWriter; import org.apache.avro.generic.GenericDatumWriter; import org.apache.avro.mapred.AvroWrapper; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.NullWritable; import org.apache.hadoop.mapreduce.RecordWriter; import org.apache.hadoop.mapreduce.TaskAttemptContext; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; /** An {@link org.apache.hadoop.mapred.OutputFormat} for Avro data files. */ public class AvroOutputFormat<T> extends FileOutputFormat<AvroWrapper<T>, NullWritable> { @Override public RecordWriter<AvroWrapper<T>, NullWritable> getRecordWriter(TaskAttemptContext context) throws IOException, InterruptedException { Schema schema = AvroJob.getMapOutputSchema(context.getConfiguration()); final DataFileWriter<T> WRITER = new DataFileWriter<T>(new GenericDatumWriter<T>()); Path path = getDefaultWorkFile(context, org.apache.avro.mapred.AvroOutputFormat.EXT); WRITER.create(schema, path.getFileSystem(context.getConfiguration()).create(path)); return new RecordWriter<AvroWrapper<T>, NullWritable>() { @Override public void write(AvroWrapper<T> wrapper, NullWritable ignore) throws IOException { WRITER.append(wrapper.datum()); } @Override public void close(TaskAttemptContext context) throws IOException, InterruptedException { WRITER.close(); } }; } }