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  • 开发中CollectionUtils处理集合

    1.org.apache.commons.collections.CollectionUtils;

    使用这个工具类,帮我们处理一些集合的操作,非常方便

    //取并集
    public
    void testUnion(){ String[] arrayA = new String[] { "A", "B", "C", "D", "E", "F" }; String[] arrayB = new String[] { "B", "D", "F", "G", "H", "K" }; List<String> listA = Arrays.asList(arrayA); List<String> listB = Arrays.asList(arrayB); //2个数组取并集 System.out.println(ArrayUtils.toString(CollectionUtils.union(listA, listB))); //[A, B, C, D, E, F, G, H, K] }
    //取交集
    public void testIntersection(){
     String[] arrayA = new String[] { "A", "B", "C", "D", "E", "F" };
     String[] arrayB = new String[] { "B", "D", "F", "G", "H", "K" }; 
    List<String> listA = Arrays.asList(arrayA); 
    List<String> listB = Arrays.asList(arrayB); 
    //2个数组取交集 
    System.out.println(ArrayUtils.toString(CollectionUtils.intersection(listA, listB)));
     //[B, D, F] }
    //取补集
    public void testDisjunction(){ 
    String[] arrayA = new String[] { "A", "B", "C", "D", "E", "F" }; 
    String[] arrayB = new String[] { "B", "D", "F", "G", "H", "K" }; 
    List<String> listA = Arrays.asList(arrayA); 
    List<String> listB = Arrays.asList(arrayB); 
    //2个数组取交集 的补集 
    System.out.println(ArrayUtils.toString(CollectionUtils.disjunction(listA, listB))); 
    //[A, C, E, G, H, K] }
    //取差集 -----------这个在项目中用到了
    public void testSubtract(){ 
    String[] arrayA = new String[] { "A", "B", "C", "D", "E", "F" }; 
    String[] arrayB = new String[] { "B", "D", "F", "G", "H", "K" }; 
    List<String> listA = Arrays.asList(arrayA); 
    List<String> listB = Arrays.asList(arrayB); 
    //arrayA扣除arrayB 
    System.out.println(ArrayUtils.toString(CollectionUtils.subtract(listA, listB)));
     //[A, C, E] }
    

    参考链接:http://www.jianshu.com/p/906d3577000b

     

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  • 原文地址:https://www.cnblogs.com/inspred/p/7646745.html
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