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Thread: Inheritance

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    Default Inheritance

    Hi I'm sort of a beginner in java, which explains some of the simple questions i may ask...
    My question now is: I'm making a small animation with java using Inheritance and methods. I've extended one of my classes from JPanel (public class Boy extends JPanel) in order to use g.fillArc to make a half circle. However, i want to extend this class (Boy) from my Main parent class (along with other moving object classes) so that i can write my main program and control the children classes. I know that i cant extend class Boy from JPanel and from Main at the same time. Is there another way to do this so that it will still inherit attributes from Main?
    Thank you!


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    Default Re: Inheritance

    There are many ways to accomplish what you are after, that being said you cannot extend a class from two parent classes (java allows multiple inheritance through interfaces however). One way is to have 'Boy' extend Main, and this can have a draw method that accepts a Graphics object. Pass this object to a new JPanel, whose paintComponent method calls the draw method
    In semi-pseudo-code:
    public abstract class MyMain{
        public abstract void draw(Graphics g);
    }
    public class MyClass extends MyMain{
     
        @Override
        public void draw(Graphics g){
            //draw here
        }
    }
     
    public class MyPanel extends JPanel{
        private final MyMain myMain;
     
        public MyPanel(MyMain m){
            myMain = m;
        }
        @Override
        public void paintComponent(Graphics g){
         ////do painting
         myMain.draw(g);
        }
    }

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    Default Re: Inheritance

    Inheritance means to acquire property of others. Using the property of other class ans functions.

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    Default Re: Inheritance

    Quote Originally Posted by samualrich123 View Post
    Inheritance means to acquire property of others. Using the property of other class ans functions.
    Not really, no. If you're going to be this vague with your definitions, you'll confuse people.

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    Default Re: Inheritance

    Inheritance means to acquire property of others. It also means that we can use code of other functions and methods. Means Code reusability. In this object are defines by classes that are super class and which classes uses property of that class is known as sub class. It is very useful in Object Oriented Languages.

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