(Analysis of Class Library Use Cases) Random Array

Use the Random class to generate 5 random integers between 1-30 (including 1 and 30)

•  Generate random array class

  class NumberFactory{
      private static Random random = new Random();
      /**
       * 通过随机数生成一个数组的内容，该内容不包括有0
       * @param length 要开辟的空间大小
       * @return  生产的数组
       */
      public static int[] create(int length){
          int data[] = new int[length];
          int foot = 0;
          while (foot < data.length){
              int num = random.nextInt(30);   //不超过30的随机数
              if(num != 0){
                  data[foot++] = num; // 保存数据
              }
          }
          return data;
      }
  }

   

• Main method

  public static void main(String[] args) {
          int[] result = NumberFactory.create(5);
          for (int x:result){
              System.out.println(x);
          }
      }

  11
  15
  5
  9
  11