hive中 udf函数Function开发

1、下载需要的jar包，创建maven工程，配置相关的pom文件
2、编写java继承UDF类  方法名必须为evaluate（）
     import java.util.List;

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

import com.ecs.accounts.bean.ChargePartyBean;
import com.ecs.accounts.util.TxtFileUtil;

public class CheckUDF extends UDF {
    public String evaluate(String P_PAY_ORG_CODE, String P_PAY_CHANNEL_CODE, String fileurl) {
        TxtFileUtil txtFile = new TxtFileUtil();
        List<ChargePartyBean> listbean = txtFile.readTxtFile(fileurl);

        for (ChargePartyBean bean : listbean) {
            String V_UDP_LEVEL = null;
            String V_MAP_CODE = null;
            String V_FIRST_PARTY = null;

            if (P_PAY_ORG_CODE == null || P_PAY_ORG_CODE.equals("")
                    && (P_PAY_CHANNEL_CODE == null || P_PAY_CHANNEL_CODE.equals(""))) {
                System.out.println("800");
                return "800";
            }

            //System.out.println("org_code:" + bean.getUDP_CODE() + "    udp_level:" + bean.getUDP_LEVEL());
            if (P_PAY_ORG_CODE.equals(bean.getUDP_CODE())) {
                V_UDP_LEVEL = bean.getUDP_LEVEL();
                V_MAP_CODE = bean.getMAP_CODE();
                if (V_UDP_LEVEL.equals("0")) {
                    System.out.println(bean.getMAP_CODE());
                    return V_MAP_CODE;
                }
                else if (V_UDP_LEVEL.equals("1")) {
                    V_FIRST_PARTY = V_MAP_CODE;
                    System.out.println("MAP_CODE:" + bean.getMAP_CODE());
                    for (ChargePartyBean listbe : listbean) {
                        if (listbe.getUDP_LEVEL().equals("2")
                                && listbe.getUDP_CODE().toUpperCase().equals(P_PAY_CHANNEL_CODE.toUpperCase())) {
                            System.out.println(V_FIRST_PARTY + listbe.getMAP_CODE());
                            return V_FIRST_PARTY + listbe.getMAP_CODE();
                        }
                    }
                }
            }

        }
        System.out.println("999");
        return "999";
    }

3、打成jar包
4、将需要的fileurl.txt 文件和jar包上传到机子上。

5、进入hive命令
6、添加需要的依赖
     ADD FILE FILEURL.TXT;

     ADD JAR TEXT.JAR;

     CREATE TEMPORARY FUNCTION TESTFUNCTION AS '执行的类路径';