1. 声明数组

   String[] arr1;
   String arr2[];
   String arr3[] = new String[5];
   String[] arr4 = new String[5]

2. 初始化数组

   // 静态初始化
   String[] arr1 = {"1", "2", "3", "4", "5"};
   String[] arr1 = new String[]{"1", "2", "3", "4", "5"};
   String arr2[] = new String[]{"1", "2", "3", "4", "5"};
   String arr2[] = {"1", "2", "3", "4", "5"};
   // 动态初始化
   int score[] = new int[3];
   for (int i = 0; i < score.length; i++) {
       score[i] = i + 1;
   }

3. 查看数组的长度

   int length = arr.length;

4. 遍历数组

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

5. int 数组转成string数组

   int[] arr = {1, 2, 3, 4, 5};
   String arrStrings = Arrays.toString(arr);
   System.out.println(arrStrings);

6. 从array中创建ArrayList