我期待到帕拉/蜂巢UDF的例子,例如:蜂巢/因帕拉UDF與字符串輸入/輸出
public class FuzzyEqualsUdf extends UDF {
public FuzzyEqualsUdf() {
}
public BooleanWritable evaluate(DoubleWritable x, DoubleWritable y) {
double EPSILON = 0.000001f;
if (x == null || y == null)
return null;
return new BooleanWritable(Math.abs(x.get() - y.get()) < EPSILON);
}
}
然後我試圖創建自己的UDF,它有字符串作爲輸入和字符串作爲輸出。理想情況下,它應該看起來像:
public class MyUdf extends UDF {
public MyUdf() {
}
public StringWritable evaluate(StringWritable x) {
String[] y = x.split(",");
String z = y[0] + "|" + y[1]
return new StringWritable(z);
}
}
不過,我的問題是有沒有StringWritable
一流!我只看到:
import org.apache.hadoop.hive.serde2.io.ByteWritable;
import org.apache.hadoop.hive.serde2.io.DoubleWritable;
import org.apache.hadoop.hive.serde2.io.ShortWritable;
import org.apache.hadoop.hive.serde2.io.TimestampWritable;
我如何用字符串類型的輸入/輸出UDF不StringWritable類?謝謝!