com.baidu.hugegraph.util

Class CollectionUtil

java.lang.Object

com.baidu.hugegraph.util.CollectionUtil

public final class CollectionUtil
extends Object

Constructor Summary

Constructors

Constructor and Description
CollectionUtil()

Method Summary

Modifier and Type	Method and Description
static boolean	allUnique(Collection<?> collection)
static <T> boolean	hasIntersection(List<T> first, Set<T> second)
static <T> boolean	hasIntersection(Set<T> first, Set<T> second)
static <T> Collection<T>	intersect(Collection<T> first, Collection<T> second) Find the intersection of two collections, the original collections will not be modified
static <T> Collection<T>	intersectWithModify(Collection<T> first, Collection<T> second) Find the intersection of two collections, note that the first collection will be modified and store the results
static <T> boolean	prefixOf(List<T> prefix, List<T> all)
static Set<Integer>	randomSet(int min, int max, int count)
static <K extends Comparable<? super K>,V> Map<K,V>	sortByKey(Map<K,V> map, boolean incr)
static <K,V extends Comparable<? super V>> Map<K,V>	sortByValue(Map<K,V> map, boolean incr)
static <T> Set<T>	subSet(Set<T> original, int from, int to) Get sub-set of a set.
static <T> List<T>	toList(Object object)
static <T> Set<T>	toSet(Object object)
static <T> Set<T>	union(Collection<T> first, Collection<T> second)

Methods inherited from class java.lang.Object

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

Constructor Detail

CollectionUtil

public CollectionUtil()

Method Detail

toSet

public static <T> Set<T> toSet(Object object)

toList

public static <T> List<T> toList(Object object)

prefixOf

public static <T> boolean prefixOf(List<T> prefix,
                                   List<T> all)

randomSet

public static Set<Integer> randomSet(int min,
                                     int max,
                                     int count)

allUnique

public static boolean allUnique(Collection<?> collection)

subSet

public static <T> Set<T> subSet(Set<T> original,
                                int from,
                                int to)

Get sub-set of a set.

Type Parameters:

T - element type of set

Parameters:

original - original set

from - index of start position

to - index of end position(exclude), but -1 means the last element

Returns:

sub-set of original set [from, to)

union

public static <T> Set<T> union(Collection<T> first,
                               Collection<T> second)

intersect

public static <T> Collection<T> intersect(Collection<T> first,
                                          Collection<T> second)

Find the intersection of two collections, the original collections will not be modified

Type Parameters:

T - element type of collection

Parameters:

first - the first collection

second - the second collection

Returns:

intersection of the two collections

intersectWithModify

public static <T> Collection<T> intersectWithModify(Collection<T> first,
                                                    Collection<T> second)

Find the intersection of two collections, note that the first collection will be modified and store the results

Type Parameters:

T - element type of collection

Parameters:

first - the first collection, it will be modified

second - the second collection

Returns:

intersection of the two collections

hasIntersection

public static <T> boolean hasIntersection(List<T> first,
                                          Set<T> second)

hasIntersection

public static <T> boolean hasIntersection(Set<T> first,
                                          Set<T> second)

sortByKey

public static <K extends Comparable<? super K>,V> Map<K,V> sortByKey(Map<K,V> map,
                                                                     boolean incr)

sortByValue

public static <K,V extends Comparable<? super V>> Map<K,V> sortByValue(Map<K,V> map,
                                                                       boolean incr)