Apache Hive Essentials

UDF code template

The code template for a regular UDF is as follows:

package com.packtpub.hive.essentials.hiveudf;
 
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.udf.UDFType; 
import org.apache.hadoop.io.Text;
// Other libraries my needed
// These information is show by "desc function <function_name>"
@Description(
 name = "udf_name",
 value = "_FUNC_(arg1, ... argN) - description for the function.",
 extended = "decription with more details, such as syntax, examples."
)
@UDFType(deterministic = true, stateful = false)

public class udf_name extends UDF {      // evaluate() is the only necessary function to overwrite
     public Text evaluate(){
         /*
          * Here to impelement core ...