org.apache.pig.scripting.jruby
Class JrubyAlgebraicEvalFunc<T>

java.lang.Object
  org.apache.pig.EvalFunc<T>
      org.apache.pig.AccumulatorEvalFunc<T>
          org.apache.pig.AlgebraicEvalFunc<T>
              org.apache.pig.scripting.jruby.JrubyAlgebraicEvalFunc<T>

All Implemented Interfaces:

Accumulator<T>, Algebraic

Direct Known Subclasses:

JrubyAlgebraicEvalFunc.BagJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.ChararrayJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.DataByteArrayJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.DoubleJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.FloatJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.IntegerJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.LongJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.MapJrubyAlgebraicEvalFunc, JrubyAlgebraicEvalFunc.TupleJrubyAlgebraicEvalFunc

public abstract class JrubyAlgebraicEvalFunc<T>
extends AlgebraicEvalFunc<T>

This class provides the bridge between Ruby classes that extend the AlgebraicPigUdf "interface" by implementing an initial, intermed, and final method. Unlike EvalFuncs and Accumulators, the type must be known at compile time (ie it can't return Object), as Pig inspects the type and ensures that it is valid. This is why class specific shells are provided at the bottom. This class leverages AlgebraicEvalFunc to provide the Accumulator and EvalFunc implementations.

Nested Class Summary

static class	JrubyAlgebraicEvalFunc.AlgebraicFunctionWrapper<T> This is a lightweight wrapper shell that registers information on the method being called, and provides the initializer that the static Algebraic classes (Initial, Intermed, Final) will use to execute.
static class	JrubyAlgebraicEvalFunc.BagJrubyAlgebraicEvalFunc Unlike EvalFuncs and Accumulators, the type must be known at compile time (ie it can't return Object), as Pig inspects the type and ensures that it is valid.
static class	JrubyAlgebraicEvalFunc.ChararrayJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.DataByteArrayJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.DoubleJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.Final<T> This class invokes the final method on the given Ruby class.
static class	JrubyAlgebraicEvalFunc.FloatJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.Initial This class invokes the initial method on the given Ruby class.
static class	JrubyAlgebraicEvalFunc.IntegerJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.Intermed This class invokes the intermed method on the given Ruby class.
static class	JrubyAlgebraicEvalFunc.LongJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.MapJrubyAlgebraicEvalFunc
static class	JrubyAlgebraicEvalFunc.TupleJrubyAlgebraicEvalFunc

Nested classes/interfaces inherited from class org.apache.pig.EvalFunc

EvalFunc.SchemaType

Field Summary

protected static BagFactory	mBagFactory
protected static TupleFactory	mTupleFactory
protected static org.jruby.Ruby	ruby
protected static org.jruby.embed.ScriptingContainer	rubyEngine

Fields inherited from class org.apache.pig.EvalFunc

log, pigLogger, reporter, returnType

Constructor Summary

JrubyAlgebraicEvalFunc(String fileName, String functionName)
The constructor takes information on the script and method being invoked and registers it with the superclass (which is necessary for AlgebraicEvalFunc).

Method Summary

abstract String	getFinal() This must be implement as per a normal Algebraic interface.
String	getInitial() This must be implement as per a normal Algebraic interface.
String	getIntermed() This must be implement as per a normal Algebraic interface.

Methods inherited from class org.apache.pig.AlgebraicEvalFunc

accumulate, cleanup, getValue

Methods inherited from class org.apache.pig.AccumulatorEvalFunc

exec

Methods inherited from class org.apache.pig.EvalFunc

finish, getArgToFuncMapping, getCacheFiles, getInputSchema, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, getSchemaType, isAsynchronous, outputSchema, 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

mBagFactory

protected static BagFactory mBagFactory

mTupleFactory

protected static final TupleFactory mTupleFactory

rubyEngine

protected static final org.jruby.embed.ScriptingContainer rubyEngine

ruby

protected static final org.jruby.Ruby ruby

Constructor Detail

JrubyAlgebraicEvalFunc

public JrubyAlgebraicEvalFunc(String fileName,
                              String functionName)

The constructor takes information on the script and method being invoked and registers it with the superclass (which is necessary for AlgebraicEvalFunc).

Method Detail

getFinal

public abstract String getFinal()

Description copied from class: AlgebraicEvalFunc

This must be implement as per a normal Algebraic interface. See Algebraic for more information.

Specified by:

getFinal in interface Algebraic

Specified by:

getFinal in class AlgebraicEvalFunc<T>

Returns:

A function name of f_final. f_final should be an eval func parametrized by the same datum as the eval func implementing this interface.

getInitial

public String getInitial()

Description copied from class: AlgebraicEvalFunc

This must be implement as per a normal Algebraic interface. See Algebraic for more information.

Specified by:

getInitial in interface Algebraic

Specified by:

getInitial in class AlgebraicEvalFunc<T>

Returns:

A function name of f_init. f_init should be an eval func. The return type of f_init.exec() has to be Tuple

getIntermed

public String getIntermed()

Description copied from class: AlgebraicEvalFunc

This must be implement as per a normal Algebraic interface. See Algebraic for more information.

Specified by:

getIntermed in interface Algebraic

Specified by:

getIntermed in class AlgebraicEvalFunc<T>

Returns:

A function name of f_intermed. f_intermed should be an eval func. The return type of f_intermed.exec() has to be Tuple