SessionId (Ratpack API (2.0.0-rc-1))

```
public interface SessionId
```
A handle to the session ID.
It is generally not necessary to use this type directly. It is used by the provided impl of Session to discover (and generate) the session ID.
The SessionModule provides a default implementation of this type that uses SessionIdGenerator, and a cookie, based on SessionCookieConfig to store the session id.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`static SessionId`	`constant(io.netty.util.AsciiString value)`	A session ID that always returns the same value.
`static SessionId`	`empty()`	A session ID that is always empty.
`io.netty.util.AsciiString`	`getValue()`	Get the session ID value, generating a new one if necessary.
`void`	`terminate()`	Terminate the current session id, disassociating it from the current user.

- Method Detail
  - getValue
```
io.netty.util.AsciiString getValue()
```
    Get the session ID value, generating a new one if necessary.
    
    Returns:
    
    the session id value
  - terminate
```
void terminate()
```
    Terminate the current session id, disassociating it from the current user.
  - constant
```
static SessionId constant(io.netty.util.AsciiString value)
```
    A session ID that always returns the same value. Suitable to use if no session ID is required, and if using client side sessions.
    
    Parameters:
    
    value - the session ID value
    
    Returns:
    
    the session ID
    
    Since:
    
    1.7
  - empty
```
static SessionId empty()
```
    A session ID that is always empty. Suitable to use if no session ID is required, and if using client side sessions.
    
    Returns:
    
    the session ID
    
    Since:
    
    1.7