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  • Re: General CS concepts

    Another note to interfaces.

    When you have an interface declared like this.

    public interface Doable
         int myInt = 10;
         boolean canDoIt1();
         int doIt2(int num);

    The code will implicitly look like this.

    public interface Doable
         [b]public static final[/b] int myInt = 10;
         [b]public[/b] boolean canDoIt1();
         [b]public[/b] int doIt2(int num);

    Notice that any variables declared in the interface will become static and final because you can only define constants on an interface.

    According to the rules of implementation the first concrete class has to implement the interface. This means that abstract classes do not have to implement the methods on the interface.

    public abstract class DoStuff implements Doable {

    // Json
    This article was originally published in forum thread: General CS concepts started by helloworld922 View original post