Spring (3.2.3), spring3.2.3

Spring (3.2.3), spring3.2.3

To create a Bean instance object, follow these steps:

• Call the constructor to create a Bean instance
• Call the static factory method to create a Bean instance
• Call the instance factory method to create a Bean instance

 

Use the constructor to create a Bean instance

XML configuration:

<bean id="exampleBean" class="examples.ExampleBean"/><bean name="anotherExample" class="examples.ExampleBeanTwo"/>

 

Create Bean instance using static factory Method

XML configuration:

<bean id="clientService" class="examples.ClientService" factory-method="createInstance"/>

Static factory class:

public class ClientService {    private static ClientService clientService = new ClientService();    private ClientService() {}    public static ClientService createInstance() {        return clientService;    }}

 

Create a Bean instance using the instance factory Method

XML configuration:

<!-- the factory bean, which contains a method called createInstance() --><bean id="serviceLocator" class="examples.DefaultServiceLocator">    <!-- inject any dependencies required by this locator bean --></bean><!-- the bean to be created via the factory bean --><bean id="clientService" factory-bean="serviceLocator" factory-method="createClientServiceInstance"/>

Instance factory type:

public class DefaultServiceLocator {    private static ClientService clientService = new ClientServiceImpl();    private DefaultServiceLocator() {}    public ClientService createClientServiceInstance() {        return clientService;    }}