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Thread: Is it possible to reference Variables from another class

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    Default Is it possible to reference Variables from another class

    Whats the best way to reference variables from another class in a project, I know how to do it to objects but not variables.

    Thanks


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    Super Moderator Norm's Avatar
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    Default Re: Is it possible to reference Variables from another class

    Add getter and setter methods to the class containing the variable and use them to get to the variable.
    Or you could make the variable public.

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    Default Re: Is it possible to reference Variables from another class

    Use static variables. They are class variables.You will always get updated values when they are altered between methods of different classes.

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    Default Re: Is it possible to reference Variables from another class

    Quote Originally Posted by rohan22 View Post
    Use static variables. They are class variables.You will always get updated values when they are altered between methods of different classes.
    This is very context dependent and often NOT the way to go about things. Norm's recommended method would be the default way to go unless you want the value of a variable to be the same across all classes.

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    Default Re: Is it possible to reference Variables from another class

    Quote Originally Posted by JoeBrown View Post
    Whats the best way to reference variables from another class in a project, I know how to do it to objects but not variables.

    Thanks
    Class variables are normally meant to be kept safe for a reason.
    When you have an exception to the rule, (only you can prevent bad code) you have options.

    Getter methods are lame, but simple and to the point, and they keep most of your protection intact.

    If your variable(number) is specific to an Object
    public class Creator {
    	private int number; // I am unique to every Creator Object
     
    	public Creator(){
    		number = 7;
    	}
     
    	public int getNumber(){ return number;}
     
    	//main method
    	public static void main(String[] args){
    		int giveMeNumber;
    		Creator user = new Creator();
     
    		giveMeNumber = user.getNumber(); // returns the number variable
    	}
    }

    If your varaible(number) is used by all Objects in the Class
    public class Creator {
    	private static int number = 7; //I exist once for all Creator Object to share me. (Should be initialized almost ALWAYS)
     
    	public static int getNumber(){ return number;} //NOTICE** the method is now static
     
    	//main method
    	public static void main(String[] args){
    		int giveMeNumber;
     
    		giveMeNumber = Creator.getNumber(); // the Class itself is used to gain permission.
     
    		//Though, this will still work and is useful in situations. (AKA: nothing wrong with it)
    		Creator user = new Creator();
    		giveMeNumber = user.getNumber(); // returns the number variable
    	}
    }

    hope this helps!
    Jonathan

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