Spring Framework example 3

DataService.java
package spring.example3;
public class DataService {
    private Consumer consumer;//object reference will be injected at runtime
    private Producer producer;//object reference will be injected at runtime

    public void execute(){
        consumer.consume(producer.produce());
    }

    public void setConsumer(Consumer consumer) {
        this.consumer = consumer;
    }

    public void setProducer(Producer producer) {
        this.producer = producer;
    }

}
Executor.java
package spring.example3;
//It uses dependency Injection
import org.springframework.beans.factory.support.*;
import org.springframework.core.io.ClassPathResource;
public class Executor {
    public static void main(String ar[]){
        DefaultListableBeanFactory bf=new DefaultListableBeanFactory();
        BeanDefinitionReader reader=new PropertiesBeanDefinitionReader(bf);
        reader.loadBeanDefinitions(new ClassPathResource("spring/example3/producer-consumer.properties"));
        DataService ds=(DataService)bf.getBean("service");
        ds.execute();
    }
}
Producer.java
package spring.example3;

public interface Producer {

    String produce();

}

Consumer.java

package spring.example3;

public interface Consumer {
    void consume(String s);
}
StringConsumer.java
package spring.example3;
public class StringConsumer implements Consumer  {
    public void consume(String s){
        System.out.println("DATA CONSUMED : "+s);
    }
}
StringProducer.java
package spring.example3;
public class StringProducer implements Producer {
    private String data="Test data ";
    public String produce(){
        return data+" : TIME - "+new java.util.Date();
    }
}

producer-consumer.properties

producer.(class)=spring.example3.StringProducer
consumer.(class)=spring.example3.StringConsumer
service.(class)=spring.example3.DataService
service.producer(ref)=producer
service.consumer(ref)=consumer