public abstract class StateManager
extends java.lang.Object
StateManager directs the process of saving and restoring the view between requests.
An implementation of this class must be thread-safe. The StateManager
instance for an application is retrieved from the Application
instance, and thus cannot know any details of
the markup language created by the RenderKit
being used to render a view.
The StateManager
utilizes a helper object (ResponseStateManager
), that is provided by the
RenderKit
implementation and is therefore aware of the markup language details.
Modifier and Type | Field and Description |
---|---|
static java.lang.String |
FULL_STATE_SAVING_VIEW_IDS_PARAM_NAME
The runtime must interpret the value of this parameter as a comma separated list of view IDs, each of which must have their state saved using the state saving mechanism specified in Jakarta Faces 1.2. |
static java.lang.String |
IS_BUILDING_INITIAL_STATE
Marker within the |
static java.lang.String |
IS_SAVING_STATE
Marker within the |
static java.lang.String |
PARTIAL_STATE_SAVING_PARAM_NAME
The |
static java.lang.String |
SERIALIZE_SERVER_STATE_PARAM_NAME
If this param is set, and calling toLowerCase().equals("true") on a String representation of its value returns true, and the jakarta.faces.STATE_SAVING_METHOD is set to "server" (as indicated below), the server state must be guaranteed to be Serializable such that the aggregate state implements java.io.Serializable. |
static java.lang.String |
STATE_SAVING_METHOD_CLIENT
Constant value for the initialization parameter named by the
STATE_SAVING_METHOD_PARAM_NAME that
indicates state saving should take place on the client. |
static java.lang.String |
STATE_SAVING_METHOD_PARAM_NAME
The
ServletContext init parameter consulted by the StateManager to tell where the state
should be saved. |
static java.lang.String |
STATE_SAVING_METHOD_SERVER
Constant value for the initialization parameter named by the
STATE_SAVING_METHOD_PARAM_NAME that
indicates state saving should take place on the server. |
Constructor and Description |
---|
StateManager() |
Modifier and Type | Method and Description |
---|---|
java.lang.String |
getViewState(FacesContext context)
Convenience method to return the view state as a |
boolean |
isSavingStateInClient(FacesContext context)
Method to determine if the state is saved on the client.
|
void |
writeState(FacesContext context,
java.lang.Object state)
Save the state represented in the specified state
Object instance, in an implementation dependent
manner. |
public static final java.lang.String STATE_SAVING_METHOD_PARAM_NAME
The ServletContext
init parameter consulted by the StateManager
to tell where the state
should be saved. Valid values are given as the values of the constants: STATE_SAVING_METHOD_CLIENT
or
STATE_SAVING_METHOD_SERVER
.
If this parameter is not specified, the default value is the value of the constant
STATE_SAVING_METHOD_CLIENT
.
public static final java.lang.String PARTIAL_STATE_SAVING_PARAM_NAME
The ServletContext
init parameter consulted by the runtime to determine if the partial state saving
mechanism should be used.
If undefined, the runtime must determine the version level of the application.
For applications versioned at 1.2 and under, the runtime must not use the partial state saving mechanism.
For applications versioned at 2.0 and above, the runtime must use the partial state saving mechanism.
If this parameter is defined, and the application is versioned at 1.2 and under, the runtime must not use the partial
state saving mechanism. Otherwise, If this param is defined, and calling toLowerCase().equals("true")
on
a String
representation of its value returns true
, the runtime must use partial state
mechanism. Otherwise the partial state saving mechanism must not be used.
public static final java.lang.String FULL_STATE_SAVING_VIEW_IDS_PARAM_NAME
The runtime must interpret the value of this parameter as a comma separated list of view IDs, each of which must have their state saved using the state saving mechanism specified in Jakarta Faces 1.2.
public static final java.lang.String IS_SAVING_STATE
Marker within the FacesContext
attributes map to indicate we are saving state. The implementation must
set this marker into the map before starting the state saving traversal and the marker must be cleared, in a
finally block, after the traversal is complete.
public static final java.lang.String IS_BUILDING_INITIAL_STATE
Marker within the FacesContext
attributes map to indicate we are marking initial state, so the
markInitialState()
method of iterating components such as UIData
could
recognize this fact and save the initial state of descendents.
public static final java.lang.String SERIALIZE_SERVER_STATE_PARAM_NAME
If this param is set, and calling toLowerCase().equals("true") on a String representation of its value returns true, and the jakarta.faces.STATE_SAVING_METHOD is set to "server" (as indicated below), the server state must be guaranteed to be Serializable such that the aggregate state implements java.io.Serializable. The intent of this parameter is to ensure that the act of writing out the state to an ObjectOutputStream would not throw a NotSerializableException, but the runtime is not required verify this before saving the state.
public static final java.lang.String STATE_SAVING_METHOD_CLIENT
Constant value for the initialization parameter named by the STATE_SAVING_METHOD_PARAM_NAME
that
indicates state saving should take place on the client.
public static final java.lang.String STATE_SAVING_METHOD_SERVER
Constant value for the initialization parameter named by the STATE_SAVING_METHOD_PARAM_NAME
that
indicates state saving should take place on the server.
public void writeState(FacesContext context, java.lang.Object state) throws java.io.IOException
Save the state represented in the specified state Object
instance, in an implementation dependent
manner.
This method will typically simply delegate the actual writing to the writeState()
method of the
ResponseStateManager
instance provided by the RenderKit
being used to render this view. This method
assumes that the caller has positioned the ResponseWriter
at the correct position for the saved state to be
written.
context
- FacesContext
for the current requeststate
- the state to be writtenjava.io.IOException
- when an I/O error occurs.public boolean isSavingStateInClient(FacesContext context)
Method to determine if the state is saved on the client.
context
- the Faces context.true
if and only if the value of the ServletContext
init parameter named by the
value of the constant STATE_SAVING_METHOD_PARAM_NAME
is equal (ignoring
case) to the value of the constant STATE_SAVING_METHOD_CLIENT
. false
otherwise.java.lang.NullPointerException
- if context
is null
.public java.lang.String getViewState(FacesContext context)
Convenience method to return the view state as a String
with no RenderKit
specific markup.
This default implementation of this method will call StateManagementStrategy.saveView(FacesContext)
and
passing the result to and returning the resulting value from
ResponseStateManager.getViewState(jakarta.faces.context.FacesContext, Object)
.
context
- FacesContext
for the current request