com.bonc.mr_roamRecognition_hjpt.comm.PathCombineTextInputFormat.java Source code

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Here is the source code for com.bonc.mr_roamRecognition_hjpt.comm.PathCombineTextInputFormat.java

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package com.bonc.mr_roamRecognition_hjpt.comm;

/**
 * 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.
 */

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathFilter;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.CombineFileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.CombineFileRecordReader;
import org.apache.hadoop.mapreduce.lib.input.CombineFileRecordReaderWrapper;
import org.apache.hadoop.mapreduce.lib.input.CombineFileSplit;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;

import com.bonc.mr_roamRecognition_hjpt.util.ProvUtil;

/**
 * Input format that is a <code>CombineFileInputFormat</code>-equivalent for
 * <code>TextInputFormat</code>.
 *
 * @see CombineFileInputFormat
 */
@InterfaceAudience.Public
@InterfaceStability.Stable
public class PathCombineTextInputFormat extends CombineFileInputFormat<Text, Text> {

    private static final Log LOG = LogFactory.getLog(PathCombineTextInputFormat.class);

    public RecordReader<Text, Text> createRecordReader(InputSplit split, TaskAttemptContext context)
            throws IOException {
        return new CombineFileRecordReader<Text, Text>((CombineFileSplit) split, context,
                TextRecordReaderWrapper.class);
    }

    /**
     * A record reader that may be passed to
     * <code>CombineFileRecordReader</code> so that it can be used in a
     * <code>CombineFileInputFormat</code>-equivalent for
     * <code>TextInputFormat</code>.
     *
     * @see CombineFileRecordReader
     * @see CombineFileInputFormat
     * @see TextInputFormat
     */
    private static class TextRecordReaderWrapper extends CombineFileRecordReaderWrapper<Text, Text> {
        // this constructor signature is required by CombineFileRecordReader
        public TextRecordReaderWrapper(CombineFileSplit split, TaskAttemptContext context, Integer idx)
                throws IOException, InterruptedException {
            super(new GetFileTextInputFormat(), split, context, idx);
        }
    }

    @Override
    public List<InputSplit> getSplits(JobContext job) throws IOException {
        List<PathFilter> filters = getPoll();
        for (int i = 0; i < filters.size(); i++) {
            PathFilter pathFilter = filters.get(i);
            createPool(pathFilter);
        }
        return super.getSplits(job);
    }

    public synchronized static List<PathFilter> getPoll() {

        List<PathFilter> pools = new ArrayList<PathFilter>();
        Map<String, String> map = ProvUtil.getCode();

        for (Map.Entry<String, String> entry : map.entrySet()) {
            final String prov_id = entry.getValue();
            pools.add(new PathFilter() {
                String provId = prov_id;

                @Override
                public boolean accept(Path path) {
                    String fileName = path.getParent().toString();
                    boolean need = fileName.endsWith(prov_id);
                    return need;
                }
            });
        }

        return pools;
    }

}