将对象作为参数传递给方法（Java）

Question

Main File

My class

The problem I am encountering is that when I attempt to compile all my program it tells me it cant find all the variables in line 17 of my main file.

I must pass the object to the printmovieinfo method.

Answer 1

Your printMovie method takes a Movie parameter named citizenkane (which is a bad name, since the method should be usable on any movie, not just that one). To get the title and other information, you'll need to tell the program that it will be getting the information from citizenkane . It won't read your mind.

The problem is that in the Movie class, you've provided methods for setting up that information, but no methods for getting the information out. In addition to set methods, you'll need get methods to get the information, like:

public String getTitle() {
    return title;
}

Then, if you have a movie object named m , you can use m.getTitle() to get the title. m.title won't work because the title field in the Movie is private , meaning it isn't visible to any other classes. Use this syntax with your citizenkane parameter to retrieve the title and other information.

Answer 2

use the reference citizenkane in printMovieInfo() , but notice that all the variables in your class Movie are private so you can't access them in printMovieInfo() . so either make them public or provide public getters for them and use them in printMovieInfo()

Answer 3

Write 'get' methods in your Movie class. These are just simple functions that return your private variables. Then access them in your main class with citizenkane.getTitle(), and so on.