Package com.github.tommyettinger.ds.support.sort

Class LongComparators

java.lang.Object

com.github.tommyettinger.ds.support.sort.LongComparators

public final class LongComparators
extends Object

A class providing static methods and objects that do useful things with comparators.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	LongComparators.NaturalImplicitComparator	A type-specific comparator mimicking the natural order.
protected static class	LongComparators.OppositeComparator
protected static class	LongComparators.OppositeImplicitComparator	A type-specific comparator mimicking the opposite of the natural order.
protected static class	LongComparators.UnsignedComparator	A type-specific comparator that compares items in the natural order, but as if they are unsigned (so, all negative items are greater than any non-negative items).
protected static class	LongComparators.UnsignedOppositeComparator	A type-specific comparator that compares items in the opposite of the natural order, but as if they are unsigned.

Field Summary

Fields

Modifier and Type	Field	Description
static final LongComparator	NATURAL_COMPARATOR
static final LongComparator	OPPOSITE_COMPARATOR
static final LongComparator	UNSIGNED_COMPARATOR
static final LongComparator	UNSIGNED_OPPOSITE_COMPARATOR

Method Summary

Modifier and Type	Method	Description
static LongComparator	asLongComparator(Comparator<? super Long> c)	Returns a type-specific comparator that is equivalent to the given comparator.
static LongComparator	oppositeComparator(LongComparator c)	Returns a comparator representing the opposite order of the given comparator.
static void	sort(long[] items, int from, int to, LongComparator c)	Sorts the specified range of elements according to the order induced by the specified comparator using mergesort.
static void	sort(long[] items, LongComparator c)	Sorts all of items by simply calling sort(long[], int, int, LongComparator), setting from and to so the whole array is sorted.

Methods inherited from class java.lang.Object

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

Field Details

NATURAL_COMPARATOR

public static final LongComparator NATURAL_COMPARATOR

OPPOSITE_COMPARATOR

public static final LongComparator OPPOSITE_COMPARATOR

UNSIGNED_COMPARATOR

public static final LongComparator UNSIGNED_COMPARATOR

UNSIGNED_OPPOSITE_COMPARATOR

public static final LongComparator UNSIGNED_OPPOSITE_COMPARATOR

Method Details

oppositeComparator

public static LongComparator oppositeComparator(LongComparator c)

Returns a comparator representing the opposite order of the given comparator.

Parameters:

c - a comparator.

Returns:

a comparator representing the opposite order of c.

asLongComparator

public static LongComparator asLongComparator(Comparator<? super Long> c)

Returns a type-specific comparator that is equivalent to the given comparator.

Parameters:

c - a comparator, or null.

Returns:

a type-specific comparator representing the order of c.

sort

public static void sort(long[] items,
 LongComparator c)

Sorts all of items by simply calling sort(long[], int, int, LongComparator), setting from and to so the whole array is sorted.

Parameters:

items - the long array to be sorted

c - a LongComparator to alter the sort order; if null, the natural order will be used

sort

public static void sort(long[] items,
 int from,
 int to,
 LongComparator c)

Sorts the specified range of elements according to the order induced by the specified comparator using mergesort.

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort. The sorting algorithm is an in-place mergesort that is significantly slower than a standard mergesort, as its running time is O(n (log n)²), but it does not allocate additional memory; as a result, it can be used as a generic sorting algorithm.

If and only if c is null, this will delegate to Arrays.sort(long[], int, int), which does not have the same guarantees regarding allocation.

Parameters:

items - the long array to be sorted

from - the index of the first element (inclusive) to be sorted.

to - the index of the last element (exclusive) to be sorted.

c - a LongComparator to alter the sort order; if null, the natural order will be used