What are the common implementations of the Application Context ?

The three commonly used implementation of 'Application Context' are

• ClassPathXmlApplicationContext : It Loads context definition from an XML file located in the classpath, treating context definitions as classpath resources. The application context is loaded from the application's classpath by using the code .

ApplicationContext context = new ClassPathXmlApplicationContext("bean.xml");
• FileSystemXmlApplicationContext : It loads context definition from an XML file in the filesystem. The application context is loaded from the file system by using the code .

ApplicationContext context = new FileSystemXmlApplicationContext("bean.xml");
• XmlWebApplicationContext : It loads context definition from an XML file contained within a web application.

How is a typical spring implementation look like ?

 For a typical Spring Application we need the following files:

• An interface that defines the functions.
• An Implementation that contains properties, its setter and getter methods, functions etc.,
• Spring AOP (Aspect Oriented Programming)
• A XML file called Spring configuration file.
• Client program that uses the function.

What is the typical Bean life cycle in Spring Bean Factory Container ?

Bean life cycle in Spring Bean Factory Container is as follows:

• The spring container finds the bean’s definition from the XML file and instantiates the bean.
• Using the dependency injection, spring populates all of the properties as specified in the bean definition
• If the bean implements the BeanNameAware interface, the factory calls setBeanName() passing the bean’s ID.
• If the bean implements the BeanFactoryAware interface, the factory calls setBeanFactory(), passing an instance of itself.
• If there are any BeanPostProcessors associated with the bean, their post- ProcessBeforeInitialization() methods will be called.
• If an init-method is specified for the bean, it will be called.
• Finally, if there are any BeanPostProcessors associated with the bean, their postProcessAfterInitialization() methods will be called.

What do you mean by Bean wiring ?

The act of creating associations between application components (beans) within the Spring container is reffered to as Bean wiring.

What do you mean by Auto Wiring?

The Spring container is able to autowire relationships between collaborating beans. This means that it is possible to automatically let Spring resolve collaborators (other beans) for your bean by inspecting the contents of the BeanFactory. The autowiring functionality has five modes.

• no
• byName
• byType
• constructor
• autodirect

What is Significance of JSF- Spring integration ?

Spring - JSF integration is useful when an event handler wishes to explicitly invoke the bean factory to create beans on demand, such as a bean that encapsulates the business logic to be performed when a submit button is pressed. 

How to integrate your Struts application with Spring?

To integrate your Struts application with Spring, we have two options:

•  Configure Spring to manage your Actions as beans, using the ContextLoaderPlugin, and set their dependencies in a Spring context file.


• Subclass Spring's ActionSupport classes and grab your Spring-managed beans explicitly using a getWebApplicationContext() method.