Menu
As we all know we have beans as singleton by default in Spring container and if we have a web application based on Spring framework then in that case do we really need to implement Singleton design pattern to hold global data rather than just creating a bean through spring.
Please bear with me if I'm not able to explain what I actually meant to ask.
646
Spring Singleton is very different from Singleton pattern. Spring guarantees to create only one bean instance for given bean id definition per container. Singleton pattern ensures that one and only one instance is created per ClassLoader.
Singleton pattern says that one and only one instance of a particular class will ever be created per classloader. The scope of a Spring singleton is described as "per container per bean". It is the scope of bean definition to a single object instance per Spring IoC container. The default scope in Spring is Singleton.
Singleton beans does not provide thread safety and now you know that instance variables usage may lead to unexpected result, you have 2 options to solve the same : Don't use instance variables in multithreaded environment.
A singleton bean in Spring and the singleton pattern are quite different. Singleton pattern says that one and only one instance of a particular class will ever be created per classloader.
The scope of a Spring singleton is described as "per container per bean". It is the scope of bean definition to a single object instance per Spring IoC container. The default scope in Spring is Singleton.
Even though the default scope is singleton, you can change the scope of bean by specifying the scope attribute of <bean ../> element.
<bean id=".." class=".." scope="prototype" /> If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
