org.apache.pig.scripting.groovy
Class GroovyEvalFunc<T>

java.lang.Object
  extended by org.apache.pig.EvalFunc<T>
      extended by org.apache.pig.scripting.groovy.GroovyEvalFunc<T>
Direct Known Subclasses:
GroovyAlgebraicEvalFunc.AlgebraicFunctionWrapper, GroovyEvalFuncObject

public class GroovyEvalFunc<T>
extends EvalFunc<T>


Nested Class Summary
 
Nested classes/interfaces inherited from class org.apache.pig.EvalFunc
EvalFunc.SchemaType
 
Field Summary
protected  Method method
           
 
Fields inherited from class org.apache.pig.EvalFunc
log, pigLogger, reporter, returnType
 
Constructor Summary
GroovyEvalFunc()
           
GroovyEvalFunc(String path, String namespace, String methodName)
           
GroovyEvalFunc(String path, String namespace, String methodName, Object target)
           
 
Method Summary
 T exec(Tuple input)
          This callback method must be implemented by all subclasses.
 Object getInvocationTarget()
           
 Schema outputSchema(Schema input)
          Report the schema of the output of this UDF.
 
Methods inherited from class org.apache.pig.EvalFunc
finish, getArgToFuncMapping, getCacheFiles, getInputSchema, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, getSchemaType, isAsynchronous, progress, setInputSchema, setPigLogger, setReporter, setUDFContextSignature, warn
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

method

protected Method method
Constructor Detail

GroovyEvalFunc

public GroovyEvalFunc()

GroovyEvalFunc

public GroovyEvalFunc(String path,
                      String namespace,
                      String methodName)
               throws IOException
Throws:
IOException

GroovyEvalFunc

public GroovyEvalFunc(String path,
                      String namespace,
                      String methodName,
                      Object target)
               throws IOException
Throws:
IOException
Method Detail

exec

public T exec(Tuple input)
       throws IOException
Description copied from class: EvalFunc
This callback method must be implemented by all subclasses. This is the method that will be invoked on every Tuple of a given dataset. Since the dataset may be divided up in a variety of ways the programmer should not make assumptions about state that is maintained between invocations of this method.

Specified by:
exec in class EvalFunc<T>
Parameters:
input - the Tuple to be processed.
Returns:
result, of type T.
Throws:
IOException

outputSchema

public Schema outputSchema(Schema input)
Description copied from class: EvalFunc
Report the schema of the output of this UDF. Pig will make use of this in error checking, optimization, and planning. The schema of input data to this UDF is provided.

The default implementation interprets the OutputSchema annotation, if one is present. Otherwise, it returns null (no known output schema).

Overrides:
outputSchema in class EvalFunc<T>
Parameters:
input - Schema of the input
Returns:
Schema of the output

getInvocationTarget

public Object getInvocationTarget()


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