实现接口类的类下的代码不执行

Question

I have an interface class called intclass. this interface class has a method called mymethod. I have created a class called impclass which implements the interface class, whithin which have the code of mymethod. however I have another method called dmeth which receives the interface intclass as a parameter. the method dmeth is in a different class called dclass. however when I run dclass, the code under mymethod does not execute. I don't understand why. below is the code:

public interface intclass{

public void mymethod(string message);
}


public class impclass 
implements intclass{

public void mymethod(String message){

System.out.println("this is the message"+message);
}

}



public class dclass{

public void dmeth(intclass cl){
....
}

public static main(String[] arg0){
impclass icl =new impclass()
dclass d=new dclass();
d.dmeth(icl);
}
}

I have no Idea on what is going wrong.. In case there is even an error concerning the expected parameter for mymethod function, I expect the error, or crashing of the program. but in my case the program run smoothly but the System.out.println("this is the message"+message); does not print. I tried to put a break in mymethod function and debug, but it was then that I realised mymethod function is not even reached. does anyone has an Idea on what ould be going on

Answer 1

String and string are not the same thing. Be aware of it when you type

public interface intclass{
    public void mymethod(string message);
}

and

public class impclass 
implements intclass{

    public void mymethod(String message){ //Note the Uppercase S
        System.out.println("this is the message"+message);
    }
}

Also, your impclass is missing a constructor, and you are not calling the method in any way. Your dmeth should contain

public void dmeth(intclass cl){
    cl.mymethod("Message");
}

in order to the mymethod to be executed.