Java中的方法/函数

对于给定的代码，我得到了指导：Java允许我们使用方法/函数，这样我们可以存储我们可能多次使用的过程，因此我希望您在方法/函数中有常见任务时更新代码。你知道怎么做吗

package fifthAssignment;

public class Arithmetic {

    public static void main(String[] args) {

        // setting up the variable firstNumber and secondNumber
        int length = args.length;

        if (length != 3) {
            System.out.println("Your suppose to enter an int, int then an operation sign like +,-,X or /.");
            return;
        }
        int firstNumber = Integer.parseInt(args[0]);
        int secondNumber = Integer.parseInt(args[1]);
        int addition = firstNumber + secondNumber;
        int minus = firstNumber - secondNumber;
        int division = firstNumber / secondNumber;
        int multiply = firstNumber * secondNumber;
        String arithmetic = args[2];

        if (arithmetic.equals("+")) {

            System.out.println(args[0] + " " + args[2] + " " + args[1] + " = " + addition);


        } else if (arithmetic.equals("-")) {

            System.out.println(args[0] + " " + args[2] + " " + args[1] + " = " + minus);


        } else if (arithmetic.equals("/")) {

            System.out.println(args[0] + " " + args[2] + " " + args[1] + " = " + division);


            // I could not use "*" operator as it was looking to pull down all
            // the files associated with this program instead of
            // using it the way I intended to use it. So in this case I changed
            // the "*" to "x" so that I can get the solution you
            // were looking for.
        } else if (arithmetic.equals("x")) {

            System.out.println(args[0] + " " + args[2] + " " + args[1] + " = " + multiply);

        }
        // following prints out to the console what the length of each argument
        // is.
        System.out.println(args[0] + " has the length of " + args[0].length());
        System.out.println(args[1] + " has the length of " + args[1].length());

        if (arithmetic.equals("+")) {
            int total = String.valueOf(addition).length();
            System.out.println(addition + " has the length of " + total);
        }else if (arithmetic.equals("-")) {
            int total = String.valueOf(minus).length();
            System.out.println(minus + " has the length of " + total);
        }else if (arithmetic.equals("/")) {
            int total = String.valueOf(division).length();
            System.out.println(division + " has the length of " + total);
        } else if (arithmetic.equals("x")) {
            int total = String.valueOf(multiply).length();
            System.out.println(multiply + " has the length of " + total);
        }

    }
}

---

我会提供一个单独的例子，但你应该自己做

您的代码中包含以下内容：

System.out.println(addition + " has the length of " + total);

相反，您可以创建一个可能使用两个int的方法：

public void printStatus(int check, int length) {
    System.out.println(check + " has the length of " + length);
}

这样你就可以打电话了

printStatus(addition, total);

---

这只是一个粗略的示例，但您可以将一个代码过程包装到一个方法中，并将执行该方法所需的必要参数传递给它。

这是基本Java。你可能需要通过一个基本的教程来了解你自己是如何做到这一点的。我想让你更新你的代码，在一个方法/函数中可以完成一些常见的任务。你如何做到这一点呢？另外，请注意，Java不是函数，而是方法。对不起，但是你的问题很懒。将来，如果你先尝试解决问题，你会得到更好的帮助。如果你不这样做，我们怎么知道你被困在哪里或是什么让你困惑？此外，你的努力也会在尊重你和你的问题方面获得很大的收获，表明你愿意付出努力和主动，首先尝试自己解决问题。我已经通过在方法中添加你的操作逻辑重新发布了解决方案。这就是我们实现模块化的方法。我修复了代码，但这与将一整块代码放到其他地方没什么不同。它不是真正的模块化，只是一分为二好吧，所以我有代码，我正在处理一些事情，试着让它工作。我现在的问题是，我无法访问performOperation方法中的变量加法、减法、除法等。我很抱歉，如果这是青少年或容易java，但我有一个问题。

package fifthAssignment;

public class Arithmetic {

    public static void main(String[] args) {

        // setting up the variable firstNumber and secondNumber
        int length = args.length;

        if (length != 3) {
            System.out.println("Your suppose to enter an int, int then an operation sign like +,-,X or /.");
            return;
        }
        int firstNumber = Integer.parseInt(args[0]);
        int secondNumber = Integer.parseInt(args[1]);
        int addition = firstNumber + secondNumber;
        int minus = firstNumber - secondNumber;
        int division = firstNumber / secondNumber;
        int multiply = firstNumber * secondNumber;
        String arithmetic = args[2];

        // following prints out to the console what the length of each argument
        // is.
        System.out.println(args[0] + " has the length of " + args[0].length());
        System.out.println(args[1] + " has the length of " + args[1].length());
        performOperation(arithmetic);
    }

    public void performOperation(String arithmetic) {
        if (arithmetic.equals("+")) {
            int total = String.valueOf(addition).length();
            System.out.println(addition + " has the length of " + total);
        } else if (arithmetic.equals("-")) {
            int total = String.valueOf(minus).length();
            System.out.println(minus + " has the length of " + total);
        } else if (arithmetic.equals("/")) {
            int total = String.valueOf(division).length();
            System.out.println(division + " has the length of " + total);
        } else if (arithmetic.equals("x")) {
            int total = String.valueOf(multiply).length();
             System.out.println(multiply + " has the length of " + total);
        }
    }

}