de.lmu.ifi.dbs.elki.utilities.pairs
Class PairUtil

java.lang.Object
  de.lmu.ifi.dbs.elki.utilities.pairs.PairUtil

public final class PairUtil
extends Object

Utility functions for Pair classes.

Author:

Erich Schubert

Nested Class Summary

static class	PairUtil.Compare<FIRST,SECOND> Compare two SimplePairs based on two comparators
static class	PairUtil.CompareByFirst<FIRST,SECOND> Compare two SimplePairs based on a comparator for the first component.
static class	PairUtil.CompareBySecond<FIRST,SECOND> Compare two SimplePairs based on a comparator for the second component.
static class	PairUtil.CompareNatural<FIRST extends Comparable<? super FIRST>,SECOND extends Comparable<? super SECOND>> Class to do a "natural order" comparison on this class.
static class	PairUtil.CompareNaturalFirst<FIRST extends Comparable<? super FIRST>,SECOND> Class to do a natural comparison on this class' first component.
static class	PairUtil.CompareNaturalSecond<FIRST,SECOND extends Comparable<? super SECOND>> Class to do a natural comparison on this class' second component.
static class	PairUtil.CompareNaturalSwapped<FIRST extends Comparable<? super FIRST>,SECOND extends Comparable<? super SECOND>> Class to do a canonical swapped comparison on this class.
static class	PairUtil.CompareSwapped<FIRST,SECOND> Compare two SimplePairs based on two comparators, but by second component first.

Constructor Summary

PairUtil()

Method Summary

static <FIRST extends Comparable<? super FIRST>,SECOND extends Comparable<? super SECOND>> Comparator<Pair<FIRST,SECOND>>	comparator() Return a comparator for this pair, given that both components are already comparable.
static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>>	comparator(Comparator<FIRST> c1, Comparator<SECOND> c2) Return a derived comparator given a comparator for each component.
static <FIRST extends Comparable<? super FIRST>,SECOND> Comparator<Pair<FIRST,SECOND>>	comparatorFirst() Return a comparator by first component for this pair, given that the first component is already comparable.
static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>>	comparatorFirst(Comparator<FIRST> c1) Return a derived comparator by first component given a comparator for this component.
static <FIRST,SECOND extends Comparable<? super SECOND>> Comparator<Pair<FIRST,SECOND>>	comparatorSecond() Return a comparator by first component for this pair, given that the first component is already comparable.
static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>>	comparatorSecond(Comparator<SECOND> c2) Return a derived comparator by first component given a comparator for this component.
static <FIRST extends Comparable<? super FIRST>,SECOND extends Comparable<? super SECOND>> Comparator<Pair<FIRST,SECOND>>	comparatorSwapped() Return a component-swapped comparator for this pair, given that both components are already comparable.
static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>>	comparatorSwapped(Comparator<FIRST> c1, Comparator<SECOND> c2) Return a derived component-swapped comparator given a comparator for each component.

Methods inherited from class java.lang.Object

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

Constructor Detail

PairUtil

public PairUtil()

Method Detail

comparator

public static <FIRST extends Comparable<? super FIRST>,SECOND extends Comparable<? super SECOND>> Comparator<Pair<FIRST,SECOND>> comparator()

Return a comparator for this pair, given that both components are already comparable. (So it could have been a CPair)

Type Parameters:

FIRST - First type

SECOND - Second type

Returns:

Comparator

comparator

public static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>> comparator(Comparator<FIRST> c1,
                                                                       Comparator<SECOND> c2)

Return a derived comparator given a comparator for each component.

Type Parameters:

FIRST - First type

SECOND - Second type

Parameters:

c1 - First comparator

c2 - Second comparator

Returns:

Comparator

comparatorFirst

public static <FIRST extends Comparable<? super FIRST>,SECOND> Comparator<Pair<FIRST,SECOND>> comparatorFirst()

Return a comparator by first component for this pair, given that the first component is already comparable. (So it could have been a FCPair)

Type Parameters:

FIRST - First type

SECOND - Second type

Returns:

Comparator

comparatorFirst

public static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>> comparatorFirst(Comparator<FIRST> c1)

Return a derived comparator by first component given a comparator for this component.

Type Parameters:

FIRST - First type

SECOND - Second type

Parameters:

c1 - Comparator for first

Returns:

Comparator

comparatorSecond

public static <FIRST,SECOND extends Comparable<? super SECOND>> Comparator<Pair<FIRST,SECOND>> comparatorSecond()

Return a comparator by first component for this pair, given that the first component is already comparable. (So it could have been a FCPair)

Type Parameters:

FIRST - First type

SECOND - Second type

Returns:

Comparator

comparatorSecond

public static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>> comparatorSecond(Comparator<SECOND> c2)

Return a derived comparator by first component given a comparator for this component.

Type Parameters:

FIRST - First type

SECOND - Second type

Parameters:

c2 - Comparator for second

Returns:

Comparator

comparatorSwapped

public static <FIRST extends Comparable<? super FIRST>,SECOND extends Comparable<? super SECOND>> Comparator<Pair<FIRST,SECOND>> comparatorSwapped()

Return a component-swapped comparator for this pair, given that both components are already comparable. (So it could have been a CPair)

Type Parameters:

FIRST - First type

SECOND - Second type

Returns:

Comparator

comparatorSwapped

public static <FIRST,SECOND> Comparator<Pair<FIRST,SECOND>> comparatorSwapped(Comparator<FIRST> c1,
                                                                              Comparator<SECOND> c2)

Return a derived component-swapped comparator given a comparator for each component.

Type Parameters:

FIRST - First type

SECOND - Second type

Parameters:

c1 - First comparator

c2 - Second comparator

Returns:

Comparator