By default, a bean does not implement any of above interfaces. Above interfaces are used for executing code blocks on specific lifecycle event on a bean, and so these are used as and when needed only. Thanks a lot Lokesh. I am clear now, as u said they are used when needed only. But,one doubt still persists. Spring container handles each and every beans life cycle defined in context.
What are those mandatory life cycle methods and these methods belongs to which interfaces? Example :- I have a single bean class, context file and Test class, and when i run Test class, which are the default methods called on the bean. Please bear my questions, which would help me lot These methods then must be defined inside bean class. Spring framework internally uses reflection to invoke these methods. Nice Explanation. I had a requirement in my project, need to run the database scripts through liquibase.
There is existing framework to check the change logs and run the change logs. So, just bean definition for this java class is enough to run the liquibase script changes for the entire project.
Now, I had another webservice client configuration class which handles the code to read the webservice url and username from database. And the table will be created and loaded with data by the above defined liquibase bean.
I have defined this webservice configuration bean as. The order of defining in spring context file is firstly,liquibase related bean and then wsClientConfig bean is defined. For me, error is coming as- no table or view exists while fetching the details of webservice fails.
I tried using depends-on but it still caused the same error. Try this. And write your logic inside afterPropertiesSet method. I have a doubt. Spring works on the top of the underline java its means JVM. Why spring beans required one more life cycle it means that already jvm will have a life cycle. JVM never tries to modify the state or behavior of an object. Spring bean life cycle is different thing. Please note that these events are not JVM triggered events.
Hi, Lokesh Thanks a lot for this meaningful blog. Hai am very new to spring. I am getting some problem in Spring bean lifecycle methods. DefaultListableBeanFactory 2a defining beans [st]; root of factory hierarchy constructor setId setName before This is init-method after This is bussinessmethod means constructor and setters methods are called two times.
The reason is — spring aop is proxy-based, i. Thanks for your reply. I understand well. Small thing is here am not using Aop concept. Plz explain me abt is there any internal relation between bean scopes and BeanPostProcessor interface methods.
Hi, Thanks for your blog. I have one requirement in my current project like i need to start a new thread in my spring application. In that thread i need to call one of the beans methods. Would you please suggest. If the object thread instance that needs access to the container is a bean in the container, just implement the BeanFactoryAware or ApplicationContextAware interfaces.
If an object outside the container needs access to the container, you must use singleton pattern for the spring container. Create this singleton bean in application startup, and set the application context reference there in a variable. Now whenever you need a bean, get the context via singleton class, and lookup the bean from application context.
Hi, Thanks a lot for this meaningful blog, I have in a problem please help me to solve it. Problem: How to prevent serialization in java if the class has implemented Serializable interface. How to prevent class B to serialize if it have behavior of serialization if someone going to serialize. Connect and share knowledge within a single location that is structured and easy to search. While learning Spring framework, I found that Spring framework provides init-method and destroy-methods which can be used to initialize some properties or to do housekeeping stuff.
We can do all those things in the bean's constructor so why do Spring provides these things and in the real world what is the actual use of these two things?
When you use setter-based dependency injection, the init-method makes it possible to perform initialization: the specified method will be called after all the setters have been called. As per destroy-method , it seems that implementing finalize in Java classes is not a good practice, instead, and many libraries define a close method which may or may not be called from finalize. Here's a few blog posts which illuminate most of the important points:. For setter injection of XML configured beans, the init-method gives you the opportunity to check the state of your object before any methods get called.
Remember there is no compile-time check that an argument is passed to initialize each field of the object. So even though a setter may be defined in the java class, the bean definition in the XML could be missing a property tag.
Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. What is the use of Spring's init-method and destroy-method?
Ask Question. Asked 9 years, 5 months ago. How to call a method after bean initialization is complete? Ask Question. Asked 12 years, 4 months ago. Active 1 year, 2 months ago. Viewed k times. How can this be done nicely? Improve this question. BalusC 1. Add a comment.
Active Oldest Votes. Improve this answer. Koray Tugay Thanks, this works. The JavaDoc for PostConstruct says that only one method can be annotated with it per class: docs. PostConstruct doesn't work with a transactional manager, see: forum. PostConstruct also won't be of much use to you when the bean you are instantiating is not a class of your own but some third party class — John Rix.
Show 1 more comment. Betlista 9, 12 12 gold badges 64 64 silver badges bronze badges. Mercer Traieste Mercer Traieste 4, 3 3 gold badges 22 22 silver badges 24 24 bronze badges. Mercer Traieste what should i give for the class attribute here?
Can i give the controller class here? There are three different approaches to consider, as described in the reference Use init-method attribute Pros: Does not require bean to implement an interface.
Cons: No immediate indication this method is required after construction to ensure the bean is correctly configured. Appropriate for beans supplied with a library, where we don't want the application using this library to concern itself with bean lifecycle.
Cons: More invasive than the init-method approach. Makes it clear that a specific method is to be used for initialisation. Intent is closer to the code. Cons: Initialisation no longer centrally specified in configuration.
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