Trying to understand the difference between the Singleton and Global-session bins areas.

If we do Singleton, the context returns the same bean.

final ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring-context.xml");

When context.getBean(SomeClass.class) is called, the same object will be returned if scope=singleton or nothing, but if we specify scope=globalSession , then the result will be the same.

But there is an implicit difference ...

And in what? How to see her? And why can it help? Thank.

    1 answer 1

    From the Spring documentation:

    Single Ion (Default) Spring IoC container.
    session Scopes HTTP session session . Only valid in the context of a web-aware Spring ApplicationContext.
    global session scopes global single session session Typically only valid when used in a Portlet context. Only valid in the context of a web-aware Spring ApplicationContext.

    singleton -bin has one instance within the entire IoC container
    session -bin has one instance within the HTTP session and dies with it:

    Session is also discarded when the HTTP Session is eventually discarded.

    globalSession -bath is almost analogous to session — it is used in portlet web applications. When you use globalSbin in a "standard" servlet application, these bins have a session -scope:

    If you are a standard HTTP session, it can be used

    But there is an implicit difference ...
    And in what? How to see her?

    To see that a session- bus has different instances in different sessions (in the "standard" spring web application), for example, you can refer to the same controller method that has this bean from 2 browser windows (one in normal mode, another in incognito).
    Example from the application at hand:

     rpfrservice.BlankServiceImpl@6f7b9a10 (1ое окно - http-сессия 1) rpfrservice.BlankServiceImpl@18d5bfc0 (2ое окно - http-сессия 2)

    When repeated requests are used all the same instances (because http-session is still alive).
    If the scope of a singleton bean, then the instance is always the same:

     rpfrservice.BlankServiceImpl@1fec9d33 (1ое окно - http-сессия 1) rpfrservice.BlankServiceImpl@1fec9d33 (2ое окно - http-сессия 2)