SessionAttribute (Spring Framework 4.3.30.RELEASE API)

```
@Target(PARAMETER)
@Retention(RUNTIME)
@Documented
public @interface SessionAttribute
```
Annotation to bind a method parameter to a session attribute.
The main motivation is to provide convenient access to existing, permanent session attributes (e.g. user authentication object) with an optional/required check and a cast to the target method parameter type.
For use cases that require adding or removing session attributes consider injecting org.springframework.web.context.request.WebRequest or javax.servlet.http.HttpSession into the controller method.
For temporary storage of model attributes in the session as part of the workflow for a controller, consider using SessionAttributes instead.
Since:
4.3
Author:
Rossen Stoyanchev
See Also:
RequestMapping, SessionAttributes, RequestAttribute

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element	Description
`String`	`name`	The name of the session attribute to bind to.
`boolean`	`required`	Whether the session attribute is required.
`String`	`value`	Alias for `name()`.

- Element Detail
  - value
```
@AliasFor("name")
String value
```
    Alias for name().
    Default:
    ""
- - name
```
@AliasFor("value")
String name
```
    The name of the session attribute to bind to.
    The default name is inferred from the method parameter name.
    Default:
    ""
- - required
```
boolean required
```
    Whether the session attribute is required.
    Defaults to true, leading to an exception being thrown if the attribute is missing in the session or there is no session. Switch this to false if you prefer a null or Java 8 java.util.Optional if the attribute doesn't exist.
    Default:
    true