Hive UDF 创建的两个例子
1. 全角到半角的转换
1 package com.scb.udf; 2 3 import org.apache.hadoop.hive.ql.exec.UDF; 4 import org.apache.hadoop.io.Text; 5 6 public class Full2Half extends UDF { 7 8 public Text evaluate(final Text input) { 9 char c[] = input.toString().toCharArray(); 10 for (int index = 0; index < c.length; index++) { 11 if (c[index] == 12288) {// 全角空格 12 c[index] = (char) 32; 13 } else if (c[index] > 65280 && c[index] < 65375) {// 其他全角字符 14 c[index] = (char) (c[index] - 65248); 15 } 16 } 17 return new Text(new String(c)); 18 } 19 20 }
2. Use hdfs file
1 package com.scb.udf; 2 3 import org.apache.hadoop.conf.Configuration; 4 import org.apache.hadoop.hive.ql.exec.UDF; 5 import org.apache.hadoop.io.Text; 6 import org.apache.hadoop.fs.*; 7 import java.io.*; 8 import java.util.Properties; 9 10 public class HadoopMap extends UDF { 11 12 13 14 public Text evaluate(final Text input) throws IOException { 15 16 org.apache.hadoop.conf.Configuration conf = new Configuration(); 17 FileSystem fs = FileSystem.get(conf); 18 Path path = new Path("/home/hypers/tmp/test.properties"); 19 InputStream inputStream = fs.open(path).getWrappedStream(); 20 Properties properties = new Properties(); 21 properties.load(inputStream); 22 String value = properties.getProperty(input.toString(),"Not Find"); 23 return new Text(value); 24 25 } 26 27 }
注册Function
hadoop fs -put -f full2half-1.0-SNAPSHOT.jar /home/hypers/lib
beeline -u jdbc:hive2://******:10000/ -n hdfs -p ****
create function hadoopmap as 'com.scb.udf.HadoopMap' using jar 'hdfs:///home/hypers/lib/full2half-1.0-SNAPSHOT.jar';
select hadoopmap("Jason");
