Java：静态方法与非静态方法

Question

I'm having a lot of trouble understanding the difference between a static method and a regular method in Java. I understand there are already a lot of questions relating to this, however none I have seen show a side by side comparison of a static and non static method accomplishing the same task.

This is the static method I have that I'm trying to change to a regular method.

public static String getString(Scanner sc, String prompt)
{
    System.out.print(prompt);
    String s = sc.next();
    sc.nextLine();
    return s;
}

And this is where I call it in another class

String productCode = Validator.getString(sc, "Enter product code: ");

How would I change this to make it a regular method and work when I call it?

Answer 1

Implementation:

public String getString(Scanner sc, String prompt)
{
    System.out.print(prompt);
    String s = sc.next();
    sc.nextLine();
    return s;
}

Usage:

new Validator(...).getString(sc , "...");

Answer 2

A method can be either static or dynamic (non static ). When a method is static , it belongs to the class. When a method is dynamic, it belongs to each specific instance of your class. That being said, removing the keyword static , creates an instance of your class and calls this method on that object.

In terms of code:

public String getString(Scanner sc, String prompt)
{

}

// Use the suitable constructor here.
Validator validator = new Validator();

String productCode = validator.getString(sc, "Enter product code: ");