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Thread: I need to retreive data from my constructor that does not have its own variable

  1. #1
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    Default I need to retreive data from my constructor that does not have its own variable

    I created a new object, and it is a parameter for a new constuctor. I can't define a value in the new constructors class for it to have a spot to save the information to, and for me to thus easily access it.

    so for example...

    private int x;
    private int y;

    public MyConstructor( int a, int b, newObject c )
    {

    x = a;
    y = b;


    }

    public newObject getNewObject()
    {
    ? help ?
    }

    any ideas?


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    Default Re: I need to retreive data from my constructor that does not have its own variable

    What specifically are you trying to accomplish?

    Format your code to preserve formatting.

    [C0DE=java]
    <code>
    [/CODE]

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    I want to get the input parameter ( my object which HAS A relationship ) by calling a get method.

    It's an assignment.

    I realize it would be incredibly easy to just define some variable... private newObject a; and then assign it in the constructor, but I can't do that. My teacher only defined those two variables in the UML.

    So... There must be some way to do it.

    --- Update ---

    Additionally, the getNewObject() is in the UML as well... just have no idea how the hell to access the data, when it's not saved to a variable somewhere... except in the main method where the instance is created... sigh...

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    help

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    I want to get the input parameter
    what is the name of the variable that is the input parameter?

    Is NewObject the class of an object that is to be returned by the getNewObject() method?
    Where is the definition/declaration of the NewObject object that is to be returned? Was the constructor supposed to create an instance of NewObject and save it in a class variable?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    Okay. Check it. I want the getMyObject() method to work without adding any new fields. I can do anything as long as it doesn't implement a new field.

     
    public class MyObject
    {   
        private int x, y;
     
        public MyObject( int xValue, int yValue )
        {
            x = xValue;
            y = yValue;
        }
     
        public int getX()
        {
            return x;
        }
        public void setX( int xValue )
        {
            x = xValue;
        }
        public int getY()
        {
            return y;
        }
        public void setY( int yValue )
        {
            y = yValue;
        }        
    }
     
    public class MyComposition
    {
        private String a, b, c;
        public MyComposition( String aValue, String bValue, String cValue, MyObject aValue )
        {
            a = aValue;
            b = bValue;
            c = cValue;
        }
     
        public MyObject getMyObject()
        {
            return aValue;
        }
    }
     
    public class MyCompositionApp
    {
        public static main( String[] args )
        {
            MyObject object = new MyObject( 5, 15 );
            MyComposition composition = new MyComposition( "This", "Is", "My", object );
     
            System.out.println( composition.getMyObject() );
     
        }    
    }
    [/highlight]

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    want the getMyObject() method to work
    Define what the method is supposed to return and where it is going to get it.
    If it's to return an object, can it create a new object every time it is called?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    where it is going to get it.
    This is my problem. I want the getMethod to return the overrided toString() of MyObject.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    Where is the instance of the MyObject class that can be used to call its toString() method?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    Error

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    Where is the instance of the MyObject class that can be used to call its toString() method?

    I don't see where the MyObject class used in the posted code.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    MyObject is a parameter of MyComposition. I didn't write the toString() method in this mock code, but it would look something like

    public String toString
    {
    return String.format( "%d, %d", x, y );
    }

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    What have you tried? What happened?

    It looks like the posted code has changed some. Is there anything worth looking at now?
    Please explain which code has the problem.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    Basically nothing, except googling for hours with no result. I have no idea how to access the object without using inheritance, or setting another variable like private MyObject x; and then defining it in the constructor.

    Maybe there's a way to access it through the package? All three are in the same package.

    The new code just shows further clarification about how the code would be used. Nothing is different except that I added a main method with instances of the classes.

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    Default Re: I need to retreive data from my constructor that does not have its own variable

    how to access the object
    What object? Is there a variable name that holds a reference to the object?
    Where does an instance of the object exist?
    If there isn't an instance, can you create one?

    What is supposed to be returned by the method? Where does the data that is supposed to be returned exist?
    If you don't understand my answer, don't ignore it, ask a question.

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