java - 将 Random 对象作为参数传递时出现问题

Question

我在传递随机对象作为参数时遇到问题。

我创建了一个新文件来测试它，但遇到了相同的错误。谁能告诉我这有什么问题吗？

import java.util.*;
public class Practice {
  public static void main(String[] args) {
    Random r = new Random(1234);
    Spring (Random r);
  }

  void Spring (Random r) {
    r.nextInt(20);
  }
}

我得到的错误是:

/tmp/Practice.java:5: error: ')' expected
    Spring (Random r);
                  ^
/tmp/Practice.java:5: error: illegal start of expression
    Spring (Random r);
                    ^
2 errors

Answer 1

您有几个问题......

这就是你应该做的(请参阅评论以获取解释):

    public static void main(String[] args) {
        Random r = new Random(1234);
        //don't need Random here
        //also call static method
        Practice.Spring (r);
}
  //since you are calling a static method, you need to declare it static
  //also it's good practice to add the methods access modifier.
  private static void Spring (Random r) {
      r.nextInt(20);
}