apache commons-collections.jar集合工具类

apache commons-collections.jar java 集合 交集 并集等

import java.util.Arrays;import java.util.Collection;import java.util.Collections;import java.util.List;import org.apache.commons.collections.CollectionUtils;import org.apache.commons.lang.ArrayUtils;public class CollectionUtilsIntro { @SuppressWarnings("unchecked") public static void main(String[] args) {  String[] arrayA = new String[] { "1", "2", "3", "3", "4", "5" };  String[] arrayB = new String[] { "3", "4", "4", "5", "6", "7" };  List<String> a = Arrays.asList(arrayA);  List<String> b = Arrays.asList(arrayB);  //并集  Collection<String> union = CollectionUtils.union(a, b);  //交集  Collection<String> intersection = CollectionUtils.intersection(a, b);  //交集的补集  Collection<String> disjunction = CollectionUtils.disjunction(a, b);  //集合相减  Collection<String> subtract = CollectionUtils.subtract(a, b);  Collections.sort((List<String>) union);  Collections.sort((List<String>) intersection);  Collections.sort((List<String>) disjunction);  Collections.sort((List<String>) subtract);  System.out.println("A: " + ArrayUtils.toString(a.toArray()));  System.out.println("B: " + ArrayUtils.toString(b.toArray()));  System.out.println("--------------------------------------------");  System.out.println("Union(A, B): " + ArrayUtils.toString(union.toArray()));  System.out.println("Intersection(A, B): " + ArrayUtils.toString(intersection.toArray()));  System.out.println("Disjunction(A, B): " + ArrayUtils.toString(disjunction.toArray()));  System.out.println("Subtract(A, B): " + ArrayUtils.toString(subtract.toArray())); }}