de.lmu.ifi.dbs.elki.datasource.filter
Class AbstractConversionFilter<I,O>

java.lang.Object
  de.lmu.ifi.dbs.elki.datasource.filter.AbstractConversionFilter<I,O>

Type Parameters:

I - Input object type

O - Input object type

All Implemented Interfaces:

ObjectFilter

Direct Known Subclasses:

AbstractFeatureSelectionFilter, AbstractNormalization, AbstractRandomFeatureSelectionFilter

public abstract class AbstractConversionFilter<I,O>
extends Object
implements ObjectFilter

Abstract base class for simple conversion filters such as normalizations and projections.

Constructor Summary

AbstractConversionFilter()

Method Summary

protected abstract SimpleTypeInformation<? super O>	convertedType(SimpleTypeInformation<I> in) Get the output type from the input type after conversion.
MultipleObjectsBundle	filter(MultipleObjectsBundle objects) A standard implementation of the filter process.
protected abstract O	filterSingleObject(I obj) Normalize a single instance.
protected abstract SimpleTypeInformation<? super I>	getInputTypeRestriction() Get the input type restriction used for negotiating the data query.
protected void	prepareComplete() Complete the initialization phase
protected void	prepareProcessInstance(I obj) Process a single object during initialization.
protected boolean	prepareStart(SimpleTypeInformation<I> in) Return "true" when the normalization needs initialization (two-pass filtering!)

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractConversionFilter

public AbstractConversionFilter()

Method Detail

filter

public MultipleObjectsBundle filter(MultipleObjectsBundle objects)

A standard implementation of the filter process. First of all, all suitable representations are found. Then (if prepareStart(de.lmu.ifi.dbs.elki.data.type.SimpleTypeInformation) returns true), the data is processed read-only in a first pass. In the main pass, each object is then filtered using filterSingleObject(I).

Specified by:

filter in interface ObjectFilter

Parameters:

objects - Object to filter

Returns:

Filtered objects

filterSingleObject

protected abstract O filterSingleObject(I obj)

Normalize a single instance. You can implement this as UnsupportedOperationException if you override both public "normalize" functions!

Parameters:

obj - Database object to normalize

Returns:

Normalized database object

getInputTypeRestriction

protected abstract SimpleTypeInformation<? super I> getInputTypeRestriction()

Get the input type restriction used for negotiating the data query.

Returns:

Type restriction

convertedType

protected abstract SimpleTypeInformation<? super O> convertedType(SimpleTypeInformation<I> in)

Get the output type from the input type after conversion.

Parameters:

in - input type restriction

Returns:

output type restriction

prepareStart

protected boolean prepareStart(SimpleTypeInformation<I> in)

Return "true" when the normalization needs initialization (two-pass filtering!)

Parameters:

in - Input type information

Returns:

true or false

prepareProcessInstance

protected void prepareProcessInstance(I obj)

Process a single object during initialization.

Parameters:

obj - Object to process

prepareComplete

protected void prepareComplete()

Complete the initialization phase