运行Mapreduce代码时，Amazon上的错误是EMR

Question

我正在将本地群集上的地图缩减代码编写为Parse XML文件。我正在使用jdom解析器。它在我的本地群集上工作正常。

但是当我试图在EMR上创建一个工作流时，它给了我以下错误：

“错误：找到类org.apache.hadoop.mapreduce.TaskAttemptContext，但接口是预期的”

我在本地计算机上使用Hadoop 0.20.2。如果有人知道问题是什么，请告诉我。

以下是记录阅读器的代码：

import java.io.IOException;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.DataOutputBuffer;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
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.TextInputFormat;


/**
   * Reads records that are delimited by a specifc begin/end tag.
 */
    public class XmlInputFormat extends  TextInputFormat {

public static final String START_TAG_KEY = "xmlinput.start";
public static final String END_TAG_KEY = "xmlinput.end";

@Override
public RecordReader<LongWritable,Text> createRecordReader(InputSplit is, TaskAttemptContext   
 tac)  {
    return new XmlRecordReader();
}
public static class XmlRecordReader extends RecordReader<LongWritable,Text> {
    private  byte[] startTag;
    private  byte[] endTag;
    private  long start;
    private  long end;
    private  FSDataInputStream fsin;
    private  DataOutputBuffer buffer = new DataOutputBuffer();
    private LongWritable key = new LongWritable();
    private Text value = new Text();



    @Override
    public void initialize(InputSplit is, TaskAttemptContext tac) throws IOException, 
     InterruptedException {
        FileSplit fileSplit= (FileSplit) is;
        startTag = tac.getConfiguration().get(START_TAG_KEY).getBytes("utf-8");
        endTag = tac.getConfiguration().get(END_TAG_KEY).getBytes("utf-8");


        start = fileSplit.getStart();
        end = start + fileSplit.getLength();
        Path file = fileSplit.getPath();

        FileSystem fs = file.getFileSystem(tac.getConfiguration());
        fsin = fs.open(fileSplit.getPath());
        fsin.seek(start);
    }

    @Override
    public boolean nextKeyValue() throws IOException, InterruptedException {
        if (fsin.getPos() < end) {
            if (readUntilMatch(startTag, false)) {
                try {
                    buffer.write(startTag);
                    if (readUntilMatch(endTag, true)) {

                        value.set(buffer.getData(), 0, 
    buffer.getLength());
                        key.set(fsin.getPos());
                        return true;
                    }
                } finally {
                    buffer.reset();
                }
            }
        }
        return false;
    }

    @Override
    public LongWritable getCurrentKey() throws IOException, InterruptedException {
        return key;
    }

    @Override
    public Text getCurrentValue() throws IOException, InterruptedException {
        return value;
    }

    @Override
    public float getProgress() throws IOException, InterruptedException {
        return (fsin.getPos() - start) / (float) (end - start);
    }

    @Override
    public void close() throws IOException {
        fsin.close();
    }
    private boolean readUntilMatch(byte[] match, boolean withinBlock) throws IOException 
      {
        int i = 0;
        while (true) {
            int b = fsin.read();
            // end of file:
            if (b == -1) return false;
            // save to buffer:
            if (withinBlock) buffer.write(b);

            // check if we're matching:
            if (b == match[i]) {
                i++;
                if (i >= match.length) return true;
            } else i = 0;
            // see if we've passed the stop point:
            if (!withinBlock && i == 0 && fsin.getPos() >= end) return false;
        }
     }

     }
       }