org.apache.giraph.reducers.impl

Class OrReduce

java.lang.Object

org.apache.giraph.reducers.ReduceSameTypeOperation<org.apache.hadoop.io.BooleanWritable>

org.apache.giraph.reducers.impl.OrReduce

All Implemented Interfaces:

ReduceOperation<org.apache.hadoop.io.BooleanWritable,org.apache.hadoop.io.BooleanWritable>, org.apache.hadoop.io.Writable

public class OrReduce
extends ReduceSameTypeOperation<org.apache.hadoop.io.BooleanWritable>

ReduceOperation for calculating the OR function over boolean values. The default value when nothing is aggregated is false.

Field Summary

Fields

Modifier and Type	Field and Description
static OrReduce	INSTANCE Instance

Constructor Summary

Constructors

Constructor and Description
OrReduce()

Method Summary

Modifier and Type	Method and Description
org.apache.hadoop.io.BooleanWritable	createInitialValue() Return new reduced value which is neutral to reduce operation.
void	readFields(DataInput in)
org.apache.hadoop.io.BooleanWritable	reduce(org.apache.hadoop.io.BooleanWritable curValue, org.apache.hadoop.io.BooleanWritable valueToReduce) Add a new value.
void	write(DataOutput out)

Methods inherited from class org.apache.giraph.reducers.ReduceSameTypeOperation

reduceMerge

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INSTANCE

public static final OrReduce INSTANCE

Instance

Constructor Detail

OrReduce

public OrReduce()

Method Detail

createInitialValue

public org.apache.hadoop.io.BooleanWritable createInitialValue()

Description copied from interface: ReduceOperation

Return new reduced value which is neutral to reduce operation.

Returns:

Neutral value

reduce

public org.apache.hadoop.io.BooleanWritable reduce(org.apache.hadoop.io.BooleanWritable curValue,
                                                   org.apache.hadoop.io.BooleanWritable valueToReduce)

Description copied from interface: ReduceOperation

Add a new value. Needs to be commutative and associative Commonly, returned value should be same as curValue argument.

Parameters:

curValue - Partial value into which to reduce and store the result

valueToReduce - Single value to be reduced

Returns:

reduced value

write

public void write(DataOutput out)
           throws IOException

Throws:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Throws:

IOException