Question

I have developed an utility class for spring which is a singleton which will provide the reference of container for the whole application , below is my class..

public class SpringUtility 
{
    private static BeanFactory factory ;
    static
    {try
        {BeanFactory factory = new XmlBeanFactory(new FileSystemResource("Spring.xml"));
        }   catch(Exception e) 
        {
            e.printStackTrace();
        }
    }

    private SpringUtility() 
    {}

    public static BeanFactory getBeanFactory()
    {       return factory;
    }}

Now please advise I want to convert it into style of eager singleton, Please advise how this could be achieved. please advise how this same class could be converted it in eager singleton design pattern such as the normal eager design pattern is ..

public class SingletonEager {

    private final static SingletonEager INSTANCE = new SingletonEager();

    private SingletonEager() {
    }

    public static SingletonEager getInstance() {
        return SingletonEager.INSTANCE;
    }

    protected Object clone() throws CloneNotSupportedException {
        throw new CloneNotSupportedException();
    }
}

similar way I want for spring one too please advise

Answer 1

If you want BeanFactory to grab beans from Spring context, then I’d suggest you to implement BeanFactoryAware, It would stay singleton & eagerly loaded

public class BeanManager implements BeanFactoryAware {

  private BeanFactory beanFactory;

  public Person getPerson(){ beanFactory.getBean(Person.class) ;}   

}

And mark this BeanManager class as spring bean