com.tinkerpop.pipes.filter

Class DuplicateFilterPipe<S>

java.lang.Object

com.tinkerpop.pipes.AbstractPipe<S,S>

com.tinkerpop.pipes.filter.DuplicateFilterPipe<S>

All Implemented Interfaces:

FilterPipe<S>, Pipe<S,S>, Iterable<S>, Iterator<S>

public class DuplicateFilterPipe<S>
extends AbstractPipe<S,S>
implements FilterPipe<S>

The DuplicateFilterPipe will not allow a duplicate object to pass through it. This is accomplished by the Pipe maintaining an internal HashSet that is used to store a history of previously seen objects. Thus, the more unique objects that pass through this Pipe, the slower it becomes as a log_2 index is checked for every object. Also, beware of OutOfMemoryExceptions as if the number of distinct objects is too great, then the HashSet will overflow memory.

Author:

Marko A. Rodriguez (http://markorodriguez.com)

Field Summary

Fields inherited from class com.tinkerpop.pipes.AbstractPipe

currentEnd, pathEnabled, starts

Fields inherited from interface com.tinkerpop.pipes.Pipe

NO_PATH_MESSAGE

Constructor Summary

Constructors

Constructor and Description
DuplicateFilterPipe()
DuplicateFilterPipe(PipeFunction<S,?> function)

Method Summary

Methods

Modifier and Type	Method and Description
protected S	processNextStart()
void	reset() A pipe may maintain state.

Methods inherited from class com.tinkerpop.pipes.AbstractPipe

enablePath, getCurrentPath, getPathToHere, hasNext, iterator, next, remove, setStarts, setStarts, setStarts, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.tinkerpop.pipes.Pipe

enablePath, getCurrentPath, setStarts, setStarts

Methods inherited from interface java.util.Iterator

hasNext, next, remove

Methods inherited from interface java.lang.Iterable

iterator

Constructor Detail

DuplicateFilterPipe

public DuplicateFilterPipe()

DuplicateFilterPipe

public DuplicateFilterPipe(PipeFunction<S,?> function)

Method Detail

processNextStart

protected S processNextStart()

Specified by:

processNextStart in class AbstractPipe<S,S>

reset

public void reset()

Description copied from interface: Pipe

A pipe may maintain state. Reset is used to remove state. The general use case for reset() is to reuse a pipe in another computation without having to create a new Pipe object. An implementation of this method should be recursive whereby the starts (if a Pipe) should have this method called on it.

Specified by:

reset in interface Pipe<S,S>

Overrides:

reset in class AbstractPipe<S,S>