<dependency>

            <groupId>org.apache.hadoop</groupId>

            <artifactId>hadoop-client</artifactId>

            <version>2.6.</version>

        </dependency>

        <dependency>

            <groupId>org.apache.hive</groupId>

            <artifactId>hive-service</artifactId>

            <version>1.2.</version>

        </dependency>

        <dependency>

            <groupId>org.apache.hive</groupId>

            <artifactId>hive-jdbc</artifactId>

            <version>1.2.</version>

        </dependency>

        <dependency>

            <groupId>org.apache.hive</groupId>

            <artifactId>hive-exec</artifactId>

            <version>1.2.</version>

        </dependency>

package com.hive.udf;

import org.apache.hadoop.hive.ql.exec.UDF;

import org.apache.hadoop.io.Text;

import java.text.ParseException;

import java.text.SimpleDateFormat;

import java.util.Date;

/**

 * Created by lenovo on 2017/10/26.

 */

public class DateTransforUDF extends UDF{

    public static final SimpleDateFormat inputFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  //匹配讲要格式化的日期格式

    public static final SimpleDateFormat outputFormat=new SimpleDateFormat("yyyyMMddHHmmss");  //要格式化的最终格式

    /*

    2013-02-17 10:38:34

    20130217103834

     */

    public Text evaluate(final Text input){

        Text output=new Text();

        if (null==input){

            return null;

        }

        String inputDate = input.toString().trim();

        if(null==inputDate){

            return null;

        }

        try {

            Date parseDate = inputFormat.parse(inputDate);

            String outputDate = outputFormat.format(parseDate);

            output.set(outputDate);

        } catch (ParseException e) {

            e.printStackTrace();

            return output;

        }

        return output;

    }

    public static void main(String[] args) {

        System.out.println(new DateTransforUDF().evaluate(new Text("2013-02-17 10:38:34")));

    }

}

hive (register_info)> add jar /root/hive_udf/BaseTest-1.0-SNAPSHOT.jar

                    > ;

Added [/root/hive_udf/BaseTest-1.0-SNAPSHOT.jar] to class path

Added resources: [/root/hive_udf/BaseTest-1.0-SNAPSHOT.jar]

hive (register_info)> create temporary function Tdate as 'com.test.OnlyDateUDF';

OK

Time taken: 0.006 seconds