I have a Spring project with auto scan and @Component annotations. Some component needs to be injected into different beans using @Autowired. Is it going to be the same component bean created as a singleton by default? If so, how can I inject different instances of the same component into different beans?
P.S. I know it's close to basics and sounds pretty general. Just wanted to make it clear for myself.
Thanks in advance
When you create a bean definition, you create a recipe for creating actual instances of the class defined by that bean definition. The idea that a bean definition is a recipe is important, because it means that, as with a class, you can create many object instances from a single recipe.
You can control not only the various dependencies and configuration values that are to be plugged into an object that is created from a particular bean definition, but also the scope of the objects created from a particular bean definition. This approach is powerful and flexible in that you can choose the scope of the objects you create through configuration instead of having to bake in the scope of an object at the Java class level. Beans can be defined to be deployed in one of a number of scopes: out of the box, the Spring Framework supports seven scopes, five of which are available only if you use a web-aware ApplicationContext.
The following scopes are supported out of the box. You can also create a custom scope.
Singleton (Default) Scopes a single bean definition to a single object instance per Spring IoC container.
Prototype Scopes a single bean definition to any number of object instances.
Request Scopes a single bean definition to the lifecycle of a single HTTP request; that is, each HTTP request has its own instance of a bean created off the back of a single bean definition. Only valid in the context of a web-aware Spring ApplicationContext.
Session Scopes a single bean definition to the lifecycle of an HTTP Session. Only valid in the context of a web-aware Spring ApplicationContext.
GlobalSession Scopes a single bean definition to the lifecycle of a global HTTP Session. Typically only valid when used in a Portlet context. Only valid in the context of a web-aware Spring ApplicationContext.
Application Scopes a single bean definition to the lifecycle of a ServletContext. Only valid in the context of a web-aware Spring ApplicationContext.
Websocket Scopes a single bean definition to the lifecycle of a WebSocket. Only valid in the context of a web-aware Spring ApplicationContext.
For more information Please visit : http://docs.spring.io/spring/docs/current/spring-framework-reference/html/
By default the scope of a Spring managed bean is singleton (only one instance is created), if you want many instances define it as prototype.
Use the following annotation:
@Scope("prototype")
Here's a good complete example: