org.apache.pig.impl.builtin
Class StreamingUDF

java.lang.Object
  extended by org.apache.pig.EvalFunc<Object>
      extended by org.apache.pig.impl.builtin.StreamingUDF

public class StreamingUDF
extends EvalFunc<Object>


Nested Class Summary
 class StreamingUDF.ProcessKiller
           
 
Nested classes/interfaces inherited from class org.apache.pig.EvalFunc
EvalFunc.SchemaType
 
Field Summary
static String TURN_ON_OUTPUT_CAPTURING
           
 
Fields inherited from class org.apache.pig.EvalFunc
pigLogger, reporter, returnType
 
Constructor Summary
StreamingUDF(String language, String filePath, String funcName, String outputSchemaString, String schemaLineNumber, String execType, String isIllustrate)
           
 
Method Summary
 Object exec(Tuple input)
          This callback method must be implemented by all subclasses.
static List<String> getResourcesForJar()
          Returns a list of file names (relative to root of pig jar) of files that need to be included in the jar shipped to the cluster.
 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

TURN_ON_OUTPUT_CAPTURING

public static final String TURN_ON_OUTPUT_CAPTURING
See Also:
Constant Field Values
Constructor Detail

StreamingUDF

public StreamingUDF(String language,
                    String filePath,
                    String funcName,
                    String outputSchemaString,
                    String schemaLineNumber,
                    String execType,
                    String isIllustrate)
             throws StreamingUDFOutputSchemaException,
                    ExecException
Throws:
StreamingUDFOutputSchemaException
ExecException
Method Detail

exec

public Object 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<Object>
Parameters:
input - the Tuple to be processed.
Returns:
result, of type T.
Throws:
IOException

getResourcesForJar

public static List<String> getResourcesForJar()
Returns a list of file names (relative to root of pig jar) of files that need to be included in the jar shipped to the cluster. Will need to be smarter as more languages are added and the controller files are large.

Returns:

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<Object>
Parameters:
input - Schema of the input
Returns:
Schema of the output


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