public final class: PolicyContext
This utility class is used by containers to communicate policy context
identifiers and other policy relevant context to Policy providers. Policy
providers use the policy context identifier to select the subset of policy
to apply in access decisions.
The value of a policy context identifier is a String and each thread has an
independently established policy context identifier. A container will
establish the thread-scoped value of a policy context identifier by calling
the static setContextID method. The value of a thread-scoped policy context
identifier is available (to Policy) by calling the static getContextID method.
This class is also used by Policy providers to request additional
thread-scoped policy relevant context objects from the calling container.
Containers register container-specific PolicyContext handlers using the
static registerHandler method. Handler registration is scoped to the class,
such that the same handler registrations are active in all thread contexts.
Containers may use the static method setHandlerData to establish a
thread-scoped parameter that will be passed to handlers when they are
activated by Policy providers. The static getContext method is used to
activate a handler and obtain the corresponding context object.
The static accessor functions provided by this class allow per-thread policy
context values to be established and communicated independent of a common
reference to a particular PolicyContext instance.
The PolicyContext class may encapsulate static ThreadLocal instance variables
to represent the policy context identifier and handler data values.
The Application server must bundle or install the PolicyContext class, and
the containers of the application server must prevent the methods of the
PolicyContext class from being called from calling contexts that are not
authorized to call these methods. With the exception of the getContextID
and GetHandlerKeys methods, containers must restrict and afford access to
the methods of the PolicyContext class to calling contexts trusted by the
container to perform container access decisions. The PolicyContext class may
satisfy this requirement (on behalf of its container) by rejecting calls made
from an AccessControlContext that has not been granted the "setPolicy"
SecurityPermission, and by ensuring that Policy providers used to perform
container access decisions are granted the "setPolicy" permission.
Scott.Stark - @jboss.org
Ron - Monzillo, Gary Ellison (javadoc)
$ - Revision: 37459 $
|Methods from java.lang.Object:|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait|
|Method from javax.security.jacc.PolicyContext Detail:|
public static Object getContext(String key) throws PolicyContextException
This method may be used by a Policy provider to activate the
PolicyContextHandler registered to the context object key and cause it to
return the corresponding policy context object from the container. When
this method activates a handler, it passes to the handler the context
object key and the handler data associated with the calling thread.
public static String getContextID()
This method returns the value of the policy context identifier associated
with the thread on which the accessor is called.
public static Set getHandlerKeys()
This method may be used to obtain the keys that identify the container
specific context handlers registered by the container.
public static void registerHandler(String key,
boolean replace) throws PolicyContextException
Authorization protected method used to register a container specific
PolicyContext handler. A handler may be registered to handle multiple keys,
but at any time, at most one handler may be registered for a key.
public static void setContextID(String contextID)
Authorization protected method used to modify the value of the policy
context identifier associated with the thread on which this method is
public static void setHandlerData(Object data)
Authorization protected method that may be used to associate a
thread-scoped handler data object with the PolicyContext. The handler data
object will be made available to handlers, where it can serve to supply or
bind the handler to invocation scoped state within the container.