org.apache.commons.betwixt.io.id
Class RandomIDGenerator

java.lang.Object
  org.apache.commons.betwixt.io.id.AbstractIDGenerator
      org.apache.commons.betwixt.io.id.RandomIDGenerator

All Implemented Interfaces:

IDGenerator

public final class RandomIDGenerator
extends AbstractIDGenerator

Generates ID's at random. The random number source is java.util.Random.

Random ID's are very useful if you're inserting elements created by Betwixt into a stream with existing elements. Using random ID's should reduce the danger of collision with existing element ID's.

This class can generate positive-only ids (the default) or it can generate a mix of negative and postive ones. This behaviour can be set by setPositiveIds(boolean) or by using the RandomIDGenerator(boolean onlyPositiveIds) constructor.

Version:

$Revision: 438373 $

Author:

Robert Burrell Donkin

Constructor Summary

RandomIDGenerator()
Constructor sets the PositiveIds property to true.

RandomIDGenerator(boolean onlyPositiveIds)
Constructor sets PositiveIds property.

Method Summary

boolean	getPositiveIds() Gets whether only positive ID's should be generated
java.lang.String	nextIdImpl() Generates a random ID.
void	setPositiveIds(boolean onlyPositiveIds) Sets whether only positive ID's should be generated

Methods inherited from class org.apache.commons.betwixt.io.id.AbstractIDGenerator

getLastId, nextId

Methods inherited from class java.lang.Object

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

Constructor Detail

RandomIDGenerator

public RandomIDGenerator()

Constructor sets the PositiveIds property to true.

RandomIDGenerator

public RandomIDGenerator(boolean onlyPositiveIds)

Constructor sets PositiveIds property.

Parameters:

onlyPositiveIds - set PositiveIds property to this value

Method Detail

nextIdImpl

public java.lang.String nextIdImpl()

Generates a random ID.

If the PositiveIds property is true, then this method will recursively call itself if the random ID is less than zero.

Specified by:

nextIdImpl in class AbstractIDGenerator

Returns:

a random integer (converted to a string)

getPositiveIds

public boolean getPositiveIds()

Gets whether only positive ID's should be generated

Returns:

whether only positive IDs should be generated

setPositiveIds

public void setPositiveIds(boolean onlyPositiveIds)

Sets whether only positive ID's should be generated

Parameters:

onlyPositiveIds - pass true if only positive IDs should be generated