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Thread: Calling a non-static method outside the package without using extends

  1. #1
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    Arrow Calling a non-static method outside the package without using extends

    Hello everyone,

    I am currently refactoring my codes and as much as possible i don't want to use static methods to avoid any conflicts when it comes to class instantiation.

    Here's my problem,

    MyClass extends OtherClass{

    private myvar;

    public getMyvar{
    return myvar
    }
    }

    OtherClassOutsidePackage {

    //How to call getMyvar?? without declaring it as static

    }

    Your idea will be very helpful. Thanks!


  2. #2
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    Default Re: Calling a non-static method outside the package without using extends

    Create a MyClass object and call the getMyvar() method.
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    Default Re: Calling a non-static method outside the package without using extends

    OtherClassOutsidePackage

    MyClass object = new MyClass();
    object.getMyVar()

    is this what you mean?

    this is not safe because the class is instantiated everytime it is called. I want only one instance created for my class to preserve the values of my instance variables.

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    Default Re: Calling a non-static method outside the package without using extends

    Then it needs to be static.
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    Default Re: Calling a non-static method outside the package without using extends

    Ok, I know it needs to be static.

    Is there anyway where I can force the compiler to get the current instance of a class ??
    What I mean is, only MyClass can instantiate an object for MyClass. Other classes must go through MyClass before they can call getMyVar()?

    In this way, it will be fine to declare getMyVar() as static.

  6. #6
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    Default Re: Calling a non-static method outside the package without using extends

    Sounds to me like you want MyClass to be a Singleton Object.

    That would look like:
    public class MyClass {
    	private static MyClass ref;
     
    	private myvar;
     
    	//Private constructor for restricted initialization
    	private MyClass() {
    		//do something, perhaps set myvar
    	}
     
    	//Method to get MyClass object
    	public static synchronized MyClass getMyClassObject() {
    		if(ref==null)
    			ref = new MyClass();
    		return ref;
    	}
     
    	//Secure against cloning
    	@Override
    	public Object clone() throws CloneNotSupportedException {
    		throw new CloneNotSupportedException();
    	}
     
    	//Your method
    	public getMyvar() {
    		return myvar;
    	}
    }

    Then, to get the myvar variable from anywhere in your program, simply call:
    //Get MyClass object
    MyClass myClass = MyClass.getMyClassObject();
    //Get variable
    myClass.getMyvar();

    It will always return the EXACT same MyClass object, regardless of how many times you call that from where ever in your program.
    Last edited by aussiemcgr; August 16th, 2012 at 03:15 PM.
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    Default Re: Calling a non-static method outside the package without using extends

    wow..this is what i'm looking for!

    thanks!

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