Hack#38

Multiply.java

package org.hadoophacks.hive;

import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.hive.serde2.io.DoubleWritable;
import java.util.*;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.IntWritable;

public class Multiply extends UDF{

    private DoubleWritable doubleResult = new DoubleWritable(0);
    private Text textResult = new Text("");

    /*
    public DoubleWritable evaluate(DoubleWritable a , DoubleWritable b){
	doubleResult.set(a.get() * b.get());
	return doubleResult;
    }
    */

    public DoubleWritable evaluate(DoubleWritable... values){
	double result = 1;

	for(DoubleWritable value : values){
	    result *= value.get();
	}

	doubleResult.set(result);
	return doubleResult;
    }

    public Text evaluate(Text orig , IntWritable num){
	int counter = num.get();
	StringBuilder builder = new StringBuilder();
	String str = orig.toString();

	for(int i = 0;i < counter;i++){
	    builder.append(str);
	}

	textResult.set(builder.toString());
	return textResult;
    }
}