[FIXED] Error while trying to do setter injection in spring via beans

Issue

Here I am trying to do setter injection of two properties

I have two interface / class pair - dependency and dependecySecond -

IDependency.java -

public interface IDependency {
    public void printDependency();
}

IDependencySecond.java -

public interface IDependencySecond {
    public void printSecondDependency();
}

Dependency.java -

public class Dependency implements IDependency {
    Dependency() {
        System.out.println("Inside dependency constructor");
    }

    @Override
    public void printDependency() {
        System.out.println("I am dependency");
    }
    
    
}

DependencySecond.java -

public class DependencySecond implements IDependencySecond {

    DependencySecond() {
        System.out.println("Inside second dependency constructor");
    }
    
    @Override
    public void printSecondDependency() {
        System.out.println("I am second depedency");
    }

}

Now I have IGame / BaseBallGame interface / class pair -

IGame.java -

public interface IGame {
    public void printDependency();
    public void playGame();
    
}

BaseBallGame.java -

public class BaseBallGame implements IGame {
    private IDependency dependency;
    private IDependencySecond dependencySecond;

    BaseBallGame(){
        System.out.println("Inside baseball game constructor");
    }
    
    public void setDependency(IDependency dependency) {
        this.dependency = dependency;
    }
    
    public void setDependencySecond(IDependencySecond dependencySecond) {
        this.dependencySecond = dependencySecond;
    }

    @Override
    public void printDependency() {
        dependency.printDependency();
    }

    @Override
    public void playGame() {
        System.out.println("Playing baseball");
    }
}

Now, at first I have the following bean code -

<bean   id="dependency"
            class="com.lonelychild.springdemo.Dependency">
    </bean>
    
    <bean   id="dependency2"
            class="com.lonelychild.springdemo.DependencySecond">
    </bean>
    
    <bean   id="game"
            class="com.lonelychild.springdemo.BaseBallGame">
        <property name="dependency" ref="dependency"></property>
    </bean>

and I have following main code -

ClassPathXmlApplicationContext context = 
                new ClassPathXmlApplicationContext("applicationContext.xml");
        
        IGame game = context.getBean("game", IGame.class);
        
        game.printDependency();
        game.playGame();
        
        context.close();

It runs without error

but when I add "dependencySecond" in bean -

<bean   id="game"
            class="com.lonelychild.springdemo.BaseBallGame">
        <property name="dependency" ref="dependency"></property>
        <property name="dependency2" ref="dependency2"></property>
    </bean>

I get

illegal depedencySecond setter method exception

So how can I add the second property?

Solution

The name of your property is work. It must mstach with the property name in the class, so:

<property name="dependency2" ref="dependency2">

must be:

 <property name="dependencySecond" ref="dependency2">

BTW: Stop using the old outdated xml configuration. Switch to the modern java based configuration.

Answered By - Jens
Answer Checked By - Cary Denson (JavaFixing Admin)