org.databene.benerator.distribution.sequence
Class ExpandGeneratorProxy<E>

java.lang.Object
  org.databene.benerator.util.AbstractGenerator<P>
      org.databene.benerator.wrapper.GeneratorWrapper<E,E>
          org.databene.benerator.wrapper.GeneratorProxy<E>
              org.databene.benerator.distribution.sequence.ExpandGeneratorProxy<E>

All Implemented Interfaces:

java.io.Closeable, Generator<E>, org.databene.commons.Resettable, org.databene.commons.ThreadAware

public class ExpandGeneratorProxy<E>
extends GeneratorProxy<E>

GeneratorProxy implementation that supports distribution of unlimited data volumes (provided by a source generator) in a unique or non-unique manner. Handling of unlimited data volume is provided with a cache of limited size, distribution is implemented by distributing source data randomly over buckets and uniqueness can be assured (when setting duplicationQuota to 0) by removing used data from its bucket.
For maximum efficiency, source data first is randomly distributed over buckets of limited size. As long as further source data is available, the proxy randomly selects an entry from a random bucket returns it to the caller and replaces it with new data if no duplicates are allowed or should not be applied in this case. If no more source data is available, the proxy returns the last element from a bucket, allowing to reduce the used bucket size without shifting elements. If a bucket is empty, it is removed.
The buckets were introduced for quickly freeing RAM after usage and for allowing a more erratic behavior in the phase when no more source data is available and elements are taken from bucket end to beginning.

Created: 10.12.2009 11:32:35

Since:

0.6.0

Author:

Volker Bergmann

Field Summary

static float	DEFAULT_DUPLICATION_QUOTA
static int	MIN_BUCKET_SIZE

Fields inherited from class org.databene.benerator.wrapper.GeneratorWrapper

source

Fields inherited from class org.databene.benerator.util.AbstractGenerator

context, state

Constructor Summary

ExpandGeneratorProxy(Generator<E> source, float duplicationQuota)

ExpandGeneratorProxy(Generator<E> source, float duplicationQuota, int cacheSize)

ExpandGeneratorProxy(Generator<E> source, float duplicationQuota, int cacheSize, int bucketSize)

Method Summary

static int	defaultBucketSize(int cacheSize)
E	generate() Returns an instance of the generic type E.
int	getBucketSize()
int	getCacheSize()
float	getDuplicationQuota()
void	init(GeneratorContext context)
void	printState()
void	reset()
void	setBucketSize(int bucketSize)
void	setCacheSize(int cacheSize)
void	setDuplicationQuota(float duplicationQuota)
static <T> ExpandGeneratorProxy<T>	uniqueProxy(Generator<T> source, int cacheSize, int bucketSize)

Methods inherited from class org.databene.benerator.wrapper.GeneratorProxy

getGeneratedType

Methods inherited from class org.databene.benerator.wrapper.GeneratorWrapper

close, equals, getSource, hashCode, isParallelizable, isThreadSafe, setSource, toString

Methods inherited from class org.databene.benerator.util.AbstractGenerator

assertInitialized, assertNotInitialized, wasInitialized

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

MIN_BUCKET_SIZE

public static final int MIN_BUCKET_SIZE

See Also:

Constant Field Values

DEFAULT_DUPLICATION_QUOTA

public static final float DEFAULT_DUPLICATION_QUOTA

See Also:

Constant Field Values

Constructor Detail

ExpandGeneratorProxy

public ExpandGeneratorProxy(Generator<E> source,
                            float duplicationQuota)

ExpandGeneratorProxy

public ExpandGeneratorProxy(Generator<E> source,
                            float duplicationQuota,
                            int cacheSize)

ExpandGeneratorProxy

public ExpandGeneratorProxy(Generator<E> source,
                            float duplicationQuota,
                            int cacheSize,
                            int bucketSize)

Method Detail

uniqueProxy

public static <T> ExpandGeneratorProxy<T> uniqueProxy(Generator<T> source,
                                                      int cacheSize,
                                                      int bucketSize)

defaultBucketSize

public static int defaultBucketSize(int cacheSize)

getCacheSize

public int getCacheSize()

setCacheSize

public void setCacheSize(int cacheSize)

getDuplicationQuota

public float getDuplicationQuota()

setDuplicationQuota

public void setDuplicationQuota(float duplicationQuota)

getBucketSize

public int getBucketSize()

setBucketSize

public void setBucketSize(int bucketSize)

init

public void init(GeneratorContext context)

Specified by:

init in interface Generator<E>

Overrides:

init in class GeneratorWrapper<E,E>

generate

public E generate()

Description copied from interface: Generator

Returns an instance of the generic type E.

Specified by:

generate in interface Generator<E>

Overrides:

generate in class GeneratorProxy<E>

reset

public void reset()

Specified by:

reset in interface org.databene.commons.Resettable

Overrides:

reset in class GeneratorWrapper<E,E>

printState

public void printState()