集合並集、交集、交集的補集、集合相減

import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.lang.ArrayUtils;

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