Package it.unimi.dsi.sux4j.mph

Class GV3CompressedFunction.Builder<T>

java.lang.Object

it.unimi.dsi.sux4j.mph.GV3CompressedFunction.Builder<T>

Enclosing class:

GV3CompressedFunction<T>

public static class GV3CompressedFunction.Builder<T>
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
protected BucketedHashStore<T>	bucketedHashStore
protected boolean	built	Whether build() has already been called.
protected Codec	codec
protected boolean	indirect
protected Iterable<? extends T>	keys
protected boolean	peeled
protected File	tempDir
protected TransformationStrategy<? super T>	transform
protected LongIterable	values

Constructor Summary

Constructors

Constructor	Description
Builder()

Method Summary

Modifier and Type	Method	Description
GV3CompressedFunction<T>	build()	Builds a new function.
GV3CompressedFunction.Builder<T>	codec(Codec codec)	Specifies a codec that will be used to encode the function output values.
GV3CompressedFunction.Builder<T>	indirect()	Specifies that the function construction must be indirect: a provided store contains indices that must be used to access the values.
GV3CompressedFunction.Builder<T>	keys(Iterable<? extends T> keys)	Specifies the keys of the function; if you have specified a BucketedHashStore, it can be null.
GV3CompressedFunction.Builder<T>	peeled()	Specifies to use peeling rather than lazy Gaussian elimination; the resulting structure uses +12% space, but it can be constructed much more quickly.
GV3CompressedFunction.Builder<T>	store(BucketedHashStore<T> bucketedHashStore)	Specifies a bucketed hash store containing the keys.
GV3CompressedFunction.Builder<T>	tempDir(File tempDir)	Specifies a temporary directory for the BucketedHashStore.
GV3CompressedFunction.Builder<T>	transform(TransformationStrategy<? super T> transform)	Specifies the transformation strategy for the keys of the function; the strategy can be raw.
GV3CompressedFunction.Builder<T>	values(LongIterable values)	Specifies the values assigned to the keys; the output width of the function will be the minimum width needed to represent all values.

Methods inherited from class java.lang.Object

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

Field Details

keys

protected Iterable<? extends T> keys

transform

protected TransformationStrategy<? super T> transform

tempDir

protected File tempDir

bucketedHashStore

protected BucketedHashStore<T> bucketedHashStore

values

protected LongIterable values

indirect

protected boolean indirect

built

protected boolean built

Whether build() has already been called.

codec

protected Codec codec

peeled

protected boolean peeled

Constructor Details

Builder

public Builder()

Method Details

keys

public GV3CompressedFunction.Builder<T> keys(Iterable<? extends T> keys)

Specifies the keys of the function; if you have specified a BucketedHashStore, it can be null.

Parameters:

keys - the keys of the function.

Returns:

this builder.

transform

public GV3CompressedFunction.Builder<T> transform(TransformationStrategy<? super T> transform)

Specifies the transformation strategy for the keys of the function; the strategy can be raw.

Parameters:

transform - a transformation strategy for the keys of the function.

Returns:

this builder.

tempDir

public GV3CompressedFunction.Builder<T> tempDir(File tempDir)

Specifies a temporary directory for the BucketedHashStore.

Parameters:

tempDir - a temporary directory for the BucketedHashStore files, or null for the standard temporary directory.

Returns:

this builder.

store

public GV3CompressedFunction.Builder<T> store(BucketedHashStore<T> bucketedHashStore)

Specifies a bucketed hash store containing the keys.

Note that if you specify a store, it is your responsibility that it conforms to the rest of the data: it must contain ranks if you do not specify values or if you use the indirect feature, values otherwise.

Parameters:

bucketedHashStore - a bucketed hash store containing the keys associated with their values and counting value frequencies, or null; the store can be unchecked, but in this case you must specify keys and a transform (otherwise, in case of a hash collision in the store an IllegalStateException will be thrown).

Returns:

this builder.

values

public GV3CompressedFunction.Builder<T> values(LongIterable values)

Specifies the values assigned to the keys; the output width of the function will be the minimum width needed to represent all values.

Parameters:

values - values to be assigned to each element, in the same order of the keys.

Returns:

this builder.

indirect

public GV3CompressedFunction.Builder<T> indirect()

Specifies that the function construction must be indirect: a provided store contains indices that must be used to access the values.

If you specify this option, the provided values must be a LongList or a LongBigList.

Returns:

this builder.

codec

public GV3CompressedFunction.Builder<T> codec(Codec codec)

Specifies a codec that will be used to encode the function output values. The default is a Codec.Huffman codec with default parameters.

Parameters:

codec - a codec that will be used to encode the function output values

Returns:

this builder.

peeled

public GV3CompressedFunction.Builder<T> peeled()

Specifies to use peeling rather than lazy Gaussian elimination; the resulting structure uses +12% space, but it can be constructed much more quickly.

Returns:

this builder.

build

public GV3CompressedFunction<T> build()
                               throws IOException

Builds a new function.

Returns:

a GOV3Function instance with the specified parameters.

Throws:

IllegalStateException - if called more than once.

IOException