| /** |
| * 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.IOException; |
| import java.util.List; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.fs.FileStatus; |
| import org.apache.hadoop.io.LongWritable; |
| import org.apache.hadoop.mapreduce.InputSplit; |
| import org.apache.hadoop.mapreduce.JobContext; |
| import org.apache.hadoop.mapreduce.RecordReader; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| |
| /** |
| * InputFormat that generates a user-defined number of splits to inject data |
| * into the database. |
| */ |
| public class ExportInputFormat |
| extends CombineFileInputFormat<LongWritable, Object> { |
| |
| public static final Log LOG = |
| LogFactory.getLog(ExportInputFormat.class.getName()); |
| |
| public static final int DEFAULT_NUM_MAP_TASKS = 4; |
| |
| public ExportInputFormat() { |
| } |
| |
| /** |
| * @return the number of bytes across all files in the job. |
| */ |
| private long getJobSize(JobContext job) throws IOException { |
| List<FileStatus> stats = listStatus(job); |
| long count = 0; |
| for (FileStatus stat : stats) { |
| count += stat.getLen(); |
| } |
| |
| return count; |
| } |
| |
| @Override |
| public List<InputSplit> getSplits(JobContext job) throws IOException { |
| // Set the max split size based on the number of map tasks we want. |
| long numTasks = getNumMapTasks(job); |
| long numFileBytes = getJobSize(job); |
| long maxSplitSize = numFileBytes / numTasks; |
| |
| setMaxSplitSize(maxSplitSize); |
| |
| LOG.debug("Target numMapTasks=" + numTasks); |
| LOG.debug("Total input bytes=" + numFileBytes); |
| LOG.debug("maxSplitSize=" + maxSplitSize); |
| |
| List<InputSplit> splits = super.getSplits(job); |
| |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Generated splits:"); |
| for (InputSplit split : splits) { |
| LOG.debug(" " + split); |
| } |
| } |
| return splits; |
| } |
| |
| @Override |
| @SuppressWarnings("unchecked") |
| public RecordReader createRecordReader( |
| InputSplit split, TaskAttemptContext context) throws IOException { |
| |
| CombineFileSplit combineSplit = (CombineFileSplit) split; |
| |
| // Use CombineFileRecordReader since this can handle CombineFileSplits |
| // and instantiate another RecordReader in a loop; do this with the |
| // CombineShimRecordReader. |
| RecordReader rr = new CombineFileRecordReader(combineSplit, context, |
| CombineShimRecordReader.class); |
| |
| return rr; |
| } |
| |
| /** |
| * Allows the user to control the number of map tasks used for this |
| * export job. |
| */ |
| public static void setNumMapTasks(JobContext job, int numTasks) { |
| job.getConfiguration().setInt(ExportJobBase.EXPORT_MAP_TASKS_KEY, numTasks); |
| } |
| |
| /** |
| * @return the number of map tasks to use in this export job. |
| */ |
| public static int getNumMapTasks(JobContext job) { |
| return job.getConfiguration().getInt(ExportJobBase.EXPORT_MAP_TASKS_KEY, |
| DEFAULT_NUM_MAP_TASKS); |
| } |
| |
| } |