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Re: Processing xml documents using StreamXmlRecordReader
Hi,
 Yes you have the class, but it's for old API.

 Please find the code below  for ported classes for new API. I have not
tested the code,try to use these classes and let me know if its working for
you.
StreamInputFormat (new API)

package org.apache.hadoop.streaming;
import java.io.IOException;
import java.lang.reflect.Constructor;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.FileSplit;
import org.apache.hadoop.mapreduce.lib.input.KeyValueTextInputFormat;
import org.apache.hadoop.streaming.StreamUtil;

/**
 * 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.
 */
/** An input format that selects a RecordReader based on a JobConf property.
 *  This should be used only for non-standard record reader such as
 *  StreamXmlRecordReader. For all other standard
 *  record readers, the appropriate input format classes should be used.
 */
public class StreamInputFormat extends KeyValueTextInputFormat {

@Override
public RecordReader<Text, Text> createRecordReader(InputSplit genericSplit,
TaskAttemptContext context) throws IOException {

Configuration conf = context.getConfiguration();
String c = conf.get("stream.recordreader.class");
if (c == null || c.indexOf("LineRecordReader") >= 0) {
return super.createRecordReader(genericSplit, context);
}

// handling non-standard record reader (likely StreamXmlRecordReader)
FileSplit split = (FileSplit) genericSplit;
//LOG.info("getRecordReader start.....split=" + split);
context.setStatus(split.toString());
context.progress();

// Open the file and seek to the start of the split
FileSystem fs = split.getPath().getFileSystem(conf);
FSDataInputStream in = fs.open(split.getPath());

// Factory dispatch based on available params..
Class readerClass;

{
readerClass = StreamUtil.goodClassOrNull(conf, c, null);
if (readerClass == null) {
throw new RuntimeException("Class not found: " + c);
}
}
Constructor ctor;
    try {
      ctor = readerClass.getConstructor(new Class[] {
FSDataInputStream.class,
                                                      FileSplit.class,
TaskAttemptContext.class, Configuration.class, FileSystem.class });
    } catch (NoSuchMethodException nsm) {
      throw new RuntimeException(nsm);
    }

    RecordReader<Text, Text> reader;
    try {
      reader = (RecordReader<Text, Text>) ctor.newInstance(new Object[] {
in, split,
                                                              context,
conf, fs });
    } catch (Exception nsm) {
      throw new RuntimeException(nsm);
    }
    return reader;
}

}

StreamXmlRecordReader

/**
 * 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.hadoop.streaming;

import java.io.*;
import java.util.regex.*;

import org.apache.hadoop.io.DataOutputBuffer;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapreduce.TaskAttemptContext;

/** A way to interpret XML fragments as Mapper input records.
 *  Values are XML subtrees delimited by configurable tags.
 *  Keys could be the value of a certain attribute in the XML subtree,
 *  but this is left to the stream processor application.
 *
 *  The name-value properties that StreamXmlRecordReader understands are:
 *    String begin (chars marking beginning of record)
 *    String end   (chars marking end of record)
 *    int maxrec   (maximum record size)
 *    int lookahead(maximum lookahead to sync CDATA)
 *    boolean slowmatch
 */
public class StreamXmlRecordReader extends StreamBaseRecordReader {

  public StreamXmlRecordReader(FSDataInputStream in, FileSplit split,
TaskAttemptContext context,
                               Configuration conf, FileSystem fs) throws
IOException {
    super(in, split, context, conf, fs);

    beginMark_ = checkJobGet(CONF_NS + "begin");
    endMark_ = checkJobGet(CONF_NS + "end");