Question

谢谢你们的帮助，对不起，对这个东西还是新手。想通了

这是我的代码

f <$> x = pure f <*> x

我收到错误消息

//Example that illustrates use of methods
public class FirstMethod
{
    //The entry point
    public void main(String[] args)
    {
        //declare two integer variables
        int firstNum = 87;
        int secondNum = 68;
        //Creating an object of the class
        FirstMethod callMethod = new FirstMethod();
        //invoking the method
        System.out.println("The result is " + 
calculateSum(firstNum,secondNum));
    }
    //creating the method.
    static int calculateSum(int first,int second)
    {
        int sum = first + second;
        return sum;
    }
}

但我不想做静态方法。请帮助是否有东西没有看到。我是新编码

Answer 1

There 'static' keyword was missing in main method, Please try this

public class FirstMethod
{
    //The entry point
    public static void main(String[] args)
    {
        //declare two integer variables
        int firstNum = 87;
        int secondNum = 68;
        //Creating an object of the class
        FirstMethod callMethod = new FirstMethod();
        //invoking the method
        System.out.println("The result is " + 
        calculateSum(firstNum,secondNum));
    }
    //creating the method.
    static int calculateSum(int first,int second)
    {
        int sum = first + second;
        return sum;
    }
}

Answer 2

简单地说，你不能。 main方法必须是静态的，因为它在创建任何对象之前被调用但是JVM。请参阅this回答。希望有所帮助。

我想创建一个非静态方法，但我也不能

2 个答案: