javax.security.jacc
Interface PolicyContextHandler
public interface PolicyContextHandler
This interface defines the methods that must be implemented by handlers that
are to be registered and activated by the PolicyContext
class.
The PolicyContext
class provides methods for containers to
register and activate container-specific PolicyContext
handlers.
Policy
providers use the PolicyContext
class to
activate handlers to obtain (from the container) additional policy relevant
context to apply in their access decisions. All handlers registered and
activated via the PolicyContext
class must implement the
PolicyContextHandler
interface.
Object | getContext(String key, Object data) - This public method is used by the
PolicyContext/ class to
activate the handler and obtain from it the the context object
identified by the (case-sensitive) key.
|
String[] | getKeys() - This public method returns the keys identifying the context objects
supported by the handler.
|
boolean | supports(String key) - This public method returns a boolean result indicating whether or not
the handler supports the context object identified by the
(case-sensitive) key value.
|
getContext
public Object getContext(String key,
Object data)
throws PolicyContextException
This public method is used by the
PolicyContext/
class to
activate the handler and obtain from it the the context object
identified by the (case-sensitive) key. In addition to the key, the
handler will be activated with the handler data value associated within
the
PolicyContext
class with the thread on which the call
to this method is made.
Note that the policy context identifier associated with a thread is
available to the handler by calling PolicyContext.getContextID().
key
- a String that identifies the context object to be returned by
the handler. The value of this paramter must not be null.data
- the handler data Object
associated with the
thread on which the call to this method has been made. Note that the
value passed through this parameter may be null.
- The container and handler specific
Object
containing the desired context. A null value may be returned if the
value of the corresponding context is null.
PolicyContextException
- if the implementation throws a checked
exception that has not been accounted for by the method signature. The
exception thrown by the implementation class will be encapsulated
(during construction) in the thrown PolicyContextException
getKeys
public String[] getKeys()
throws PolicyContextException
This public method returns the keys identifying the context objects
supported by the handler. The value of each key supported by a handler
must be a non-null String value.
- an array containing String values identifing the context objects
supported by the handler. The array must not contain duplicate key
values. In the unlikely case that the Handler supports no keys, the
handler must return a zero length array. The value null must never be
returned by this method.
PolicyContextException
- if the implementation throws a checked
exception that has not been accounted for by the method signature. The
exception thrown by the implementation class will be encapsulated
(during construction) in the thrown PolicyContextException
supports
public boolean supports(String key)
throws PolicyContextException
This public method returns a boolean result indicating whether or not
the handler supports the context object identified by the
(case-sensitive) key value.
key
- a String
The value of this parameter
must not be null.
- a boolean indicating whether or not the context object
corresponding to the argument key is handled by the handler.
PolicyContextException
- if the implementation throws a checked
exception that has not been accounted for by the method signature. The
exception thrown by the implementation class will be encapsulated
(during construction) in the thrown PolicyContextException