调用：

//重复项有9、5、1、2

        int[] ints = new int[]{9,4,7,8,2,5,1,6,2,5,9,1};

        arrayIntTest(ints);

        /////////////////////////////

        //重复项有9、5、1、2

        Integer[] integers = new Integer[]{9,4,7,8,2,5,1,6,2,5,9,1};

        arrayIntegerTest(integers);

        /////////////////////////////

        //重复项有e、g

        String[] strs = new String[]{"e","t","a","d","g","c","A","f","e","g","Q","h"};

        arrayStringTest(strs);

 /**

     * int[]数组操作 正序、倒叙、去重

     * @param arr

     */

    public static void arrayIntTest(int[] arr) {

        int length = arr.length;

        //int[]正序

        Arrays.sort(arr);

        //int[]倒序

        Arrays.sort(arr);

        ArrayUtils.reverse(arr);

        System.out.print("");

        //int[]正序

        int[] arr1 = Arrays.stream(arr).boxed().sorted().mapToInt(p -> p).toArray();

        System.out.print("");

        //int[]倒序

        int[] arr2 = Arrays.stream(arr).boxed().sorted((s1, s2) -> {return s2 > s1 ? 1 : -1;}).mapToInt(p -> p).toArray();

        System.out.print("");

        //int[]去重

        int[] arr3 = Arrays.stream(arr).boxed().distinct().mapToInt(p -> p).toArray();

    }

    /**

     * Integer[]数组操作 正序、倒叙、去重

     * @param arr

     */

    public static void arrayIntegerTest(Integer[] arr){

        int length = arr.length;

        //Integer[]正序

        Arrays.sort(arr);

        //Integer[]倒序

        Arrays.sort(arr, Collections.reverseOrder());

        //Integer[]倒序

        Arrays.sort(arr);

        ArrayUtils.reverse(arr);

        //Integer[]去重

        Set<Integer> set = new HashSet<Integer>();

        set.addAll(Arrays.asList(arr));

        Integer[] arr4 = new Integer[set.size()];

        set.toArray(arr4);

        //Integer[]正序，去重

        Set set1=new TreeSet(Arrays.asList(arr));

        Integer[] arr5 = new Integer[set1.size()];

        set1.toArray(arr5);

        //Integer[]正序

        Integer[] arr1 = new Integer[arr.length];

        Arrays.stream(arr).sorted().collect(Collectors.toList()).toArray(arr1);

        //Integer[]倒序

        Integer[] arr2 = new Integer[arr.length];

        Arrays.stream(arr).sorted((s1, s2) -> {return s2>s1?1:-1;}).collect(Collectors.toList()).toArray(arr2);

        //Integer[]去重

        List<Integer> list1 =  Arrays.stream(arr).distinct().collect(Collectors.toList());

        Integer[] arr3 = new Integer[list1.size()];

        list1.toArray(arr3);

    }

    /**

     * String[] 操作 正序、倒叙、去重

     * @param arr

     */

    public static void arrayStringTest(String[] arr){

        int length = arr.length;

        //String[]正序

        Arrays.sort(arr);

        //String[]倒序

        Arrays.sort(arr, Collections.reverseOrder());

        //String[]正序 不区分大小写

        Arrays.sort(arr, String.CASE_INSENSITIVE_ORDER);

        //String[]倒序 不区分大小写

        Arrays.sort(arr, String.CASE_INSENSITIVE_ORDER);

        Collections.reverse(Arrays.asList(arr));

        //String[]去重

        Set<String> set = new HashSet<String>();

        set.addAll(Arrays.asList(arr));

        String[] arr4 = new String[set.size()];

        set.toArray(arr4);

        //String[]正序，去重

        Set set1=new TreeSet(Arrays.asList(arr));

        String[] arr5 = new String[set1.size()];

        set1.toArray(arr5);

        //String[]去重

        List<String> list1 =  Arrays.stream(arr).distinct().collect(Collectors.toList());

        String[] arr1 = new String[list1.size()];

        list1.toArray(arr1);

    }