| /** |
| * 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.sqoop.mapreduce; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.mapreduce.JobContext; |
| import org.apache.hadoop.mapreduce.OutputCommitter; |
| import org.apache.hadoop.mapreduce.OutputFormat; |
| import org.apache.hadoop.mapreduce.RecordWriter; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| import org.apache.hadoop.util.ReflectionUtils; |
| import org.apache.sqoop.lib.FieldMappable; |
| import org.apache.sqoop.lib.FieldMapProcessor; |
| import org.apache.sqoop.lib.ProcessingException; |
| |
| /** |
| * OutputFormat that produces a RecordReader which instantiates |
| * a FieldMapProcessor which will process FieldMappable |
| * output keys. |
| * |
| * <p>The output value is ignored.</p> |
| * |
| * <p>The FieldMapProcessor implementation may do any arbitrary |
| * processing on the object. For example, it may write an object |
| * to HBase, etc.</p> |
| * |
| * <p>If the FieldMapProcessor implementation also implements |
| * Closeable, it will be close()'d in the RecordReader's close() |
| * method.</p> |
| * |
| * <p>If the FMP implements Configurable, it will be configured |
| * correctly via ReflectionUtils.</p> |
| */ |
| public class DelegatingOutputFormat<K extends FieldMappable, V> |
| extends OutputFormat<K, V> { |
| |
| /** conf key: the FieldMapProcessor class to instantiate. */ |
| public static final String DELEGATE_CLASS_KEY = |
| "sqoop.output.delegate.field.map.processor.class"; |
| |
| @Override |
| /** {@inheritDoc} */ |
| public void checkOutputSpecs(JobContext context) |
| throws IOException, InterruptedException { |
| Configuration conf = context.getConfiguration(); |
| |
| if (null == conf.get(DELEGATE_CLASS_KEY)) { |
| throw new IOException("Delegate FieldMapProcessor class is not set."); |
| } |
| } |
| |
| @Override |
| /** {@inheritDoc} */ |
| public OutputCommitter getOutputCommitter(TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| return new NullOutputCommitter(); |
| } |
| |
| @Override |
| /** {@inheritDoc} */ |
| public RecordWriter<K, V> getRecordWriter(TaskAttemptContext context) |
| throws IOException { |
| try { |
| return new DelegatingRecordWriter(context); |
| } catch (ClassNotFoundException cnfe) { |
| throw new IOException(cnfe); |
| } |
| } |
| |
| /** |
| * RecordWriter to write the output to a row in a database table. |
| * The actual database updates are executed in a second thread. |
| */ |
| public class DelegatingRecordWriter extends RecordWriter<K, V> { |
| |
| private Configuration conf; |
| |
| private FieldMapProcessor mapProcessor; |
| |
| public DelegatingRecordWriter(TaskAttemptContext context) |
| throws ClassNotFoundException { |
| |
| this.conf = context.getConfiguration(); |
| |
| @SuppressWarnings("unchecked") |
| Class<? extends FieldMapProcessor> procClass = |
| (Class<? extends FieldMapProcessor>) |
| conf.getClass(DELEGATE_CLASS_KEY, null); |
| this.mapProcessor = ReflectionUtils.newInstance(procClass, this.conf); |
| } |
| |
| protected Configuration getConf() { |
| return this.conf; |
| } |
| |
| @Override |
| /** {@inheritDoc} */ |
| public void close(TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| if (mapProcessor instanceof Closeable) { |
| ((Closeable) mapProcessor).close(); |
| } |
| } |
| |
| @Override |
| /** {@inheritDoc} */ |
| public void write(K key, V value) |
| throws InterruptedException, IOException { |
| try { |
| mapProcessor.accept(key); |
| } catch (ProcessingException pe) { |
| throw new IOException(pe); |
| } |
| } |
| } |
| } |