String[] arr1 = new String[5];

 String[] arr2 = {"a","b","c", "d", "e"};

 String[] arr3= new String[]{"a","b","c","d","e"};  

 int[] arr = { 1, 2, 3, 4, 5 };

 String arrString = Arrays.toString(arr);  

 // 直接输出，为内存地址

 System.out.println(arr);

 // [I@139a55

 System.out.println(arrString );

 // [1, 2, 3, 4, 5]  

 String[] arr= { "a", "b", "c", "d", "e" };

 boolean b = Arrays.asList(arr).contains("a");

 System.out.println(b);

 // true  

 //使用Apache Commons Lang library

 1 int[] arr1 = { 1, 2, 3, 4, 5 };

 2 int[] arr2= { 6, 7, 8, 9, 10 };

 3 int[] combArr = ArrayUtils.addAll(arr1 , arr2); 

// System.arraycopy()
1 static String[] concat(String[] a, String[] b) {

       String[] c = new String[a.length + b.length];

       System.arraycopy(a, 0, c, 0, a.length);

       System.arraycopy(b, 0, c, a.length, b.length);

       return c;

  }

 //Arrays.copyOf()

 public static int[] concat(int[] first, int[] second) {

     int[] result = Arrays.copyOf(first, first.length + second.length);

     System.arraycopy(second, 0, result, first.length, second.length);

     return result;

 }

 // Apache Commons Lang library

 int[] arr= { 1, 2, 3, 4, 5 };

 ArrayUtils.reverse(intArray);

 System.out.println(Arrays.toString(intArray));

 //[5, 4, 3, 2, 1]  

 int[] arr = { 1, 2, 3, 4, 5 };

 int[] revArr = new int[arr.length];

 for(int i = 0; i < arr.length; i++){

     revArr[i] = arr[arr.length - i -1];

 }

 System.out.println(Arrays.toString(revArr));

 //[5, 4, 3, 2, 1]

 // Apache common lang  

 int[] arr= { 1, 2, 3, 4, 5 };

 int[] removed = ArrayUtils.removeElement(intArray, 3);//create a new array

 System.out.println(Arrays.toString(removed))