FactoryBean
A factory bean in Spring serves as a factory for creating other beans within the Spring IoC container. A FactoryBean is an interface that you, as a developer, implements when writing factory classes and you want the object created by the factory to be managed as a bean by Spring.
In Java terms we can say that, a factory bean is very similar to a factory method (Java Factory Pattern).
But here it is Spring specific bean which can be identified by the Spring IoC container during bean construction.
Factory is mostly used to implement framework specific operations.
1. Suppose when you are looking for JNDI related stuffs then JndiObjectFactoryBean can be used.
2. For Spring AOP related stuffs (create a proxy for a bean) we can use ProxyFactoryBean.
3. For creating Hibernate Session Factory in the Spring IoC container then we can use LocalSessionFactoryBean.
Difference between BeanFactory and FactoryBean in Spring Framework