How do I get some variable from another class in Java

Question

I am  playing around  with Java  watching tutorials and trying to get the hang of it  For this question  I m trying to figure out how I can take a variable from another class and use it in my main one  without making the initial variable public  Here is the code   I am trying to get int x equal to 5  as seen in the setNum   method   but when it prints it gives me 0   Main Class   package getVarTest   public class Main        public static void main  String  args           Vars varsObject   new Vars            int x   varsObject getNum            System out println x             Variable Class   package getVarTest       public class Vars           private int num              public void setNum int x                   this num   5                            public int getNum                    return num                        So  as you can see I am trying to take the private int num and make the int x in the main class equal to it

User · Answer

You never call varsObject setNum

User · Answer

I am trying to get int x equal to 5  as seen in the setNum   method  but when it prints it gives me 0    To run the code in setNum you have to call it   If you don t call it  the default value is 0

User · Answer

Do NOT do that  setNum num    fix- until someone fixes your setter  Your getter should not call your setter with the uninitialized value ofnum e g 0     I suggest making a few small changes -   public static class Vars     private int num   5     Default to 5     public void setNum int x        this num   x     actually  set  the value         public int getNum         return num

User · Answer

Your example is perfect  the field is private and it has a getter  This is the normal way to access a field  If you need a direct access to an object field  use reflection  Using reflection to get a field s value is a hack and should be used in extreme cases such as using a library whose code you cannot change

User · Answer

The code that you have is correct  To get a variable from another class you need to create an instance of the class if the variable is not static  and just call the explicit method to get access to that variable  If you put get and set method like the above is the same of declaring that variable public   Put the method setNum private and inside the getNum assign the value that you want  you will have  get  access to the variable in that case

[java] How do I get some variable from another class in Java?

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