TextDistributedCacheFileReader.java

package com.manning.hip.ch4.joins.replicated;

import org.apache.commons.io.*;
import org.apache.commons.lang.StringUtils;

import java.io.*;
import java.util.Iterator;

public class TextDistributedCacheFileReader
    implements DistributedCacheFileReader<String, String>, Iterator<Pair<String, String>> {
  LineIterator iter;

  @Override
  public void init(File f) throws IOException {
    iter = FileUtils.lineIterator(f);
  }

  @Override
  public void close() {
    iter.close();
  }

  @Override
  public Iterator<Pair<String, String>> iterator() {
    return this;
  }

  @Override
  public boolean hasNext() {
    return iter.hasNext();
  }

  @Override
  public Pair<String, String> next() {
    String line = iter.next();
    Pair<String, String> pair = new Pair<String, String>();
    String[] parts = StringUtils.split(line, "\t", 2);
    pair.setKey(parts[0]);
    if(parts.length > 1) {
      pair.setData(parts[1]);
    }
    return pair;
  }

  @Override
  public void remove() {
    throw new UnsupportedOperationException();
  }
}