如何将输出文件名从减速机中的part-00000更改为inputfile名称

Question

目前，我能够在mapper中实现从part-00000到自定义文件名的名称更改。我通过使用输入拆分来实现这一点。我在reducer中尝试了同样的方法来重命名文件，但fileSplit方法不适用于reducer。那么，有没有最好的方法将reducer的输出重命名为inputfile name呢。下面是我如何在mapper中实现的。

@Override
    public void setup(Context con) throws IOException, InterruptedException {
        fileName = ((FileSplit) con.getInputSplit()).getPath().getName();
        fileName = fileName.substring(0,36);
        outputName = new Text(fileName);  

        final Path baseOutputPath = FileOutputFormat.getOutputPath(con);
        final Path outputFilePath = new Path(baseOutputPath, fileName);
        TextOutputFormat<IntWritable, Text> write = new TextOutputFormat<IntWritable, Text>() {
        @Override
        public Path getDefaultWorkFile(TaskAttemptContext context, String extension) throws IOException {
        return outputFilePath;

Answer 1

这是hadoop wiki说的：

You can subclass the OutputFormat.java class and write your own. You can locate and browse the code of TextOutputFormat, MultipleOutputFormat.java, etc. for reference. It might be the case that you only need to do minor changes to any of the existing Output Format classes. To do that you can just subclass that class and override the methods you need to change. 

如果需要使用键和输入文件格式，那么可以创建MultipleOutputFormat的子类来控制输出文件名。