追随我心

package com.randyho.hadoop.converter;
 
import java.io.DataInputStream;
import java.io.IOException;
 
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
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.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.FileSplit;
 
import com.randyho.FetcherOutput;
 
public class ConverterInputFormat extends FileInputFormat<Text, FetcherOutput> {
 
  // Do not split files.
  protected boolean isSplitable(JobContext context, Path file) {
    return false;
  }
 
  public RecordReader<Text, FetcherOutput> createRecordReader(
      InputSplit split, TaskAttemptContext context) throws IOException,
      InterruptedException {
    return new ConvertertRecordReader();
  }
 
  class ConvertertRecordReader extends RecordReader<Text, FetcherOutput> {
 
    private DataInputStream dis;
    private Text key = null;
    private FetcherOutput value;
    private boolean more = true;
    private Configuration conf;
 
    public ConvertertRecordReader(){
      key = new Text();
      value = new FetcherOutput();
      more = true;
    }
 
    public void close() throws IOException {
      if (dis != null) {
        dis.close();
      }
    }
 
    public Text getCurrentKey() throws IOException, InterruptedException {
      return key;
    }
 
    public FetcherOutput getCurrentValue() throws IOException,
        InterruptedException {
      return value;
    }
 
    public float getProgress() throws IOException, InterruptedException {
      return more ? 0f : 100f;
    }
 
    public void initialize(InputSplit gensplit, TaskAttemptContext context)
        throws IOException, InterruptedException {
      FileSplit split = (FileSplit) gensplit;
      conf = context.getConfiguration();  
      Path file = split.getPath();
      FileSystem fs = file.getFileSystem(conf);
 
      System.out.println("reading: " + file);
 
      // open the file
      dis = fs.open(split.getPath());
    }
 
    public boolean nextKeyValue() throws IOException, InterruptedException {
      if (dis.available() != 0) {
        value.readFields(dis);
        key.set(value.getUrl());        
        return true;
      } else {
        more = false;
        return false;
      }
    }
  }
}