How to autowire byName using interface

[Om Prakash Bijawat]

Hi ,

This is my interface:

public interface QuizMaster {
	public String popQuestion();
}

These are my two implementation classes :

public class SpringQuizMaster implements QuizMaster{
	
	public String popQuestion() {
		return "Spring Quessonaire";
	}
}


public class StrutsQuizMaster implements QuizMaster{
	
	public String popQuestion() {
		return "Struts Quessonaire";
	}
}

And this is my service class :

public class QuizMasterService {

	QuizMaster quiz = null;
	public QuizMasterService(QuizMaster quizMaster) {
		this.quiz = quizMaster;
	}

	public void setQuiz(QuizMaster quizMaster) {
		this.quiz = quizMaster;
	}

                  public void askQuestions() {
		System.out.println(quiz.popQuestion());
	}
}

my Main method :

public class ExecutableClass {
private ApplicationContext ctx = null;
private QuizMasterService quizService = null;
public static void main(String args[]){
		ExecutableClass exeClass = new ExecutableClass();
		ctx = new ClassPathXmlApplicationContext("master-quiz.xml");		
                                   exeClass.getQuestions();
		quizService = (QuizMasterService)ctx.getBean("quizMasterService");
		}
}

In my master-quiz.xml file I have written :

<bean id = "springQuizMaster" class ="com.services.SpringQuizMaster"></bean>
<bean id = "strutsQuizMaster" class = "com.services.StrutsQuizMaster"></bean>
<bean id = "quizMasterService" class = "com.services.QuizMasterService" init-method = "init" destroy-method = "destroy" autowire="byName">

When I use :

<constructor-arg ref="springQuizMaster"/> instead of autowire attribute it runs perfect

but while using autowiring it fails.
Can anyone help me out?
Thanks

[Jeanne Boyarsky]

You can't autowire here without more information because there are two beans that go with that constructor. Spring has no way to know which bean you want injected. That's why it works when you use the constructor.