如何对多个输入文件仅使用一个Map？因为hadoop为一个文件创建了一个Map器。我只需要一个Map所有文件。
我试着用 CombineFileInputFormat . 它有一个Map器，但Map输入只包含一个文件。我需要输入Map值来包含来自所有文件（文本格式）的数据，如下所示：
输入Map值：
来自file1.txt的数据
来自file2.txt的数据
来自file3.txt的数据

public class WholeFileInputFormat extends CombineFileInputFormat<NullWritable, Text> {

public WholeFileInputFormat() {
    super();
    setMaxSplitSize(67108864);
}

@Override
protected boolean isSplitable(JobContext context, Path file) {
    return false;
}

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

    if (!(split instanceof CombineFileSplit)) {
        throw new IllegalArgumentException("split must be a CombineFileSplit");
    }
    RecordReader<NullWritable, Text> r = new CombineFileRecordReader<NullWritable, Text>((CombineFileSplit) split, context, WholeFileRecordReader.class);
    return r;
    //return null;
}

}

public class WholeFileRecordReader extends RecordReader<NullWritable, Text> {

private final Text mFileText;

public WholeFileRecordReader(CombineFileSplit fileSplit, TaskAttemptContext context,
                             Integer pathToProcess) throws IOException {

    mProcessed = false;
    mFileToRead = fileSplit.getPath(pathToProcess);
    mFileLength = fileSplit.getLength(pathToProcess);
    mConf = context.getConfiguration();

    assert 0 == fileSplit.getOffset(pathToProcess);
    FileSystem fs = FileSystem.get(mConf);
    assert fs.getFileStatus(mFileToRead).getLen() == mFileLength;

    //    mFileName = new Text();
    mFileText = new Text();
}

@Override
public void close() throws IOException {
    mFileText.clear();
}

@Override
public NullWritable getCurrentKey() throws IOException, InterruptedException {
    return NullWritable.get();
}

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

@Override
public float getProgress() throws IOException, InterruptedException {
    return (mProcessed) ? (float) 1.0 : (float) 0.0;
}

@Override
public void initialize(InputSplit split, TaskAttemptContext context)
        throws IOException, InterruptedException {
    // no-op.
}

@Override
public boolean nextKeyValue() throws IOException, InterruptedException {
    if (!mProcessed) {
        if (mFileLength > (long) Integer.MAX_VALUE) {
            throw new IOException("File is longer than Integer.MAX_VALUE.");
        }
        byte[] contents = new byte[(int) mFileLength];

        FileSystem fs = mFileToRead.getFileSystem(mConf);
        FSDataInputStream in = null;
        try {
            // Set the contents of this file.
            in = fs.open(mFileToRead);
            IOUtils.readFully(in, contents, 0, contents.length);
            mFileText.set(contents, 0, contents.length);

        } finally {
            IOUtils.closeStream(in);
        }
        mProcessed = true;
        return true;
    }
    return false;
}
}

你能帮我吗？