org.apache.hadoop.hive.ql.udf.generic
Class GenericUDFWhen
java.lang.Object
org.apache.hadoop.hive.ql.udf.generic.GenericUDF
org.apache.hadoop.hive.ql.udf.generic.GenericUDFWhen
- All Implemented Interfaces:
- Closeable
public class GenericUDFWhen
- extends GenericUDF
GenericUDF Class for SQL construct
"CASE WHEN a THEN b WHEN c THEN d [ELSE f] END".
NOTES: 1. a and c should be boolean, or an exception will be thrown. 2. b, d
and f should be common types, or an exception will be thrown.
GenericUDFWhen
public GenericUDFWhen()
initialize
public ObjectInspector initialize(ObjectInspector[] arguments)
throws UDFArgumentTypeException
- Description copied from class:
GenericUDF
- Initialize this GenericUDF. This will be called once and only once per
GenericUDF instance.
- Specified by:
initialize
in class GenericUDF
- Parameters:
arguments
- The ObjectInspector for the arguments
- Returns:
- The ObjectInspector for the return value
- Throws:
UDFArgumentTypeException
evaluate
public Object evaluate(GenericUDF.DeferredObject[] arguments)
throws HiveException
- Description copied from class:
GenericUDF
- Evaluate the GenericUDF with the arguments.
- Specified by:
evaluate
in class GenericUDF
- Parameters:
arguments
- The arguments as DeferedObject, use DeferedObject.get() to get the
actual argument Object. The Objects can be inspected by the
ObjectInspectors passed in the initialize call.
- Returns:
- The
- Throws:
HiveException
getDisplayString
public String getDisplayString(String[] children)
- Description copied from class:
GenericUDF
- Get the String to be displayed in explain.
- Specified by:
getDisplayString
in class GenericUDF
Copyright © 2014 The Apache Software Foundation. All rights reserved.