com.envision.eeop.api.util

类 SetUtils

java.lang.Object

com.envision.eeop.api.util.SetUtils

public class SetUtils
extends Object

Set Utility

构造器概要

构造器

构造器和说明
SetUtils()

方法概要

方法

限定符和类型	方法和说明
protected static <T> T	checkNotNull(T reference, String errorMessage) Ensures that an object reference passed as a parameter to the calling method is not null.
static <E> List<E>	difference(Collection<? extends E> set1, Collection<? extends E> set2) Returns a list of the difference of two sets.
static <E> List<E>	union(Collection<? extends E> set1, Collection<? extends E> set2) Returns a list of the union of two sets.

从类继承的方法 java.lang.Object

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

构造器详细资料

SetUtils

public SetUtils()

方法详细资料

checkNotNull

protected static <T> T checkNotNull(T reference,
                 String errorMessage)

Ensures that an object reference passed as a parameter to the calling method is not null.

参数:

reference - an object reference

errorMessage - the exception message to use if the check fails

返回:

the non-null reference that was validated

抛出:

NullPointerException - if reference is null

difference

public static <E> List<E> difference(Collection<? extends E> set1,
                     Collection<? extends E> set2)

Returns a list of the difference of two sets. The returned set contains all elements that are contained by set1 and not contained by set2. set2 may also contain elements not present in set1; these are simply ignored. The iteration order of the returned set matches that of set1.

union

public static <E> List<E> union(Collection<? extends E> set1,
                Collection<? extends E> set2)

Returns a list of the union of two sets. The returned set contains all elements that are contained in either backing set. Iterating over the returned set iterates first over all the elements of set1, then over each element of set2, in order, that is not contained in set1.

Note: The returned view performs better when set1 is the smaller of the two sets. If you have reason to believe one of your sets will generally be smaller than the other, pass it first.