CompositeKey.java

package hip.ch6.joins.repartition.impl;

import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.io.WritableComparator;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

public class CompositeKey implements WritableComparable<CompositeKey> {

  private String key = "";
  private long order = 0;

  public CompositeKey() {
  }

  public CompositeKey(String key, long order) {
    this.key = key;
    this.order = order;
  }

  public String getKey() {
    return this.key;
  }

  public long getOrder() {
    return this.order;
  }

  public void setKey(String key) {
    this.key = key;
  }

  public void setOrder(long order) {
    this.order = order;
  }

  @Override
  public void readFields(DataInput in) throws IOException {
    this.key = in.readUTF();
    this.order = in.readLong();
  }

  @Override
  public void write(DataOutput out) throws IOException {
    out.writeUTF(key);
    out.writeLong(this.order);
  }

  @Override
  public int compareTo(CompositeKey other) {
    if (this.key.compareTo(other.key) != 0) {
      return this.key.compareTo(other.key);
    } else if (this.order != other.order) {
      return order < other.order ? -1 : 1;
    } else {
      return 0;
    }
  }

  public static class CompositeKeyComparator extends WritableComparator {
    public CompositeKeyComparator() {
      super(CompositeKey.class);
    }

    public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
      return compareBytes(b1, s1, l1, b2, s2, l2);
    }
  }

  @Override
  public String toString() {
    return ToStringBuilder.reflectionToString(this);
  }


  static { // register this comparator
    WritableComparator.define(CompositeKey.class,
        new CompositeKeyComparator());
  }
}