java - 将一个程序分成两个不同的类

Question

所以我必须编写一个代码，接受一个单词并反转它，我让它工作，但为了我的家庭作业，我必须将它分成两个类，一个测试类和一个主类，我该怎么做？

public static void main(String args[])
{
  String original = "";
  String reverse = "";
  Scanner in = new Scanner(System.in);

  System.out.println("Enter a string to reverse");
  original = in.nextLine();

  int length = original.length();

  for ( int i = length - 1 ; i >= 0 ; i-- )
  {
     reverse = reverse + original.charAt(i);
  }
  System.out.println("Reverse of entered string is: "+reverse);
}

Answer 1

您创建了两个类。您甚至可以在两者中都添加一个 main 方法。

public class Homework {
    public static void main(String[] args) {
        // Code here to prompt user for string and to print reversed string
    }
    static String reverse(String input) {
        // Code here to do the actual reverse logic, returning reversed string
    }
}

public class HomeworkTest {
    public static void main(String[] args) {
        test("Hello", "olleH");
        test("This is a test", "tset a si sihT");
    }
    private static void test(String input, String expected) {
        String rev = Homework.reverse(input);
        System.out.println(input + ": " + rev);
        if (! expected.equals(rev))
            System.out.println("  ** NOT AS EXPECTED: " + expected);
    }
}

您现在可以运行 Homework 进行手动测试，或运行 HomeworkTest 类进行自动测试。