求两个数组的交集。

使用retainAll()方法来计算两个数组的交集。

完整代码

import java.util.ArrayList;public class Main {public static void main(String[] args)  {ArrayList objArray = new ArrayList();ArrayList objArray2 = new ArrayList();objArray2.add(0,"common1");objArray2.add(1,"common2");objArray2.add(2,"notcommon");objArray2.add(3,"notcommon1");objArray.add(0,"common1");objArray.add(1,"common2");objArray.add(2,"notcommon2");System.out.println("array1 数组元素："+objArray);System.out.println("array2 数组元素："+objArray2);objArray.retainAll(objArray2);System.out.println("array2 & array1 数组交集为："+objArray);}
}

结果输出

array1 数组元素：[common1, common2, notcommon2]
array2 数组元素：[common1, common2, notcommon, notcommon1]
array2 & array1 数组交集为：[common1, common2]