org.fourthline.cling.model.ServiceManager< T > Interface Template Reference

Binds the metadata of a service to a service implementation, unified interface for accessing local services. More...

Inheritance diagram for org.fourthline.cling.model.ServiceManager< T >:

Collaboration diagram for org.fourthline.cling.model.ServiceManager< T >:

Public Member Functions
LocalService< T >	getService ()
T	getImplementation ()
void	execute (Command< T > cmd) throws Exception
	Double-dispatch of arbitrary commands, used by action executors and state variable accessors.
PropertyChangeSupport	getPropertyChangeSupport ()
	Provides the capability to monitor the service for state changes.
Collection< StateVariableValue >	getCurrentState () throws Exception
	Reading the state of a service manually.

Static Public Attributes
static final String	EVENTED_STATE_VARIABLES = "_EventedStateVariables"
	Use this property name when propagating change events that affect any evented UPnP state variable.

Detailed Description

Binds the metadata of a service to a service implementation, unified interface for accessing local services.

The UPnP core will always access a local service implementation through this manager, available with org.fourthline.cling.model.meta.LocalService#getManager():

• The org.fourthline.cling.model.action.ActionExecutors use the manager to process UPnP control invocations. It's the service manager's job to translate such an action invocation into an actual method invocation, or any other procedure that satisfies the requirements. The org.fourthline.cling.model.action.ActionExecutor works together with the manager, for example, the org.fourthline.cling.model.action.MethodActionExecutor expects that an action method can be invoked through reflection on the instance returned by the manager's getImplementation() method. This is possible with the the org.fourthline.cling.model.DefaultServiceManager. A different service manager might require a different set of action executors, and vice versa.
• The org.fourthline.cling.model.state.StateVariableAccessors use the manager to process UPnP state variable queries and GENA eventing. It's the service manager's job to return an actual value when a state variable has to be read. The org.fourthline.cling.model.state.StateVariableAccessor works together with the service manager, for example, the org.fourthline.cling.model.state.FieldStateVariableAccessor expects that a state variable value can be read through reflection on a field, of the instance returned by getImplementation(). This is possible with the org.fourthline.cling.model.DefaultServiceManager. A different service manager might require a different set of state variable accessors, and vice versa.
• A service manager has to notify the UPnP core, and especially the GENA eventing system, whenever the state of any evented UPnP state variable changes. For new subscriptions GENA also has to read the current state of the service manually, when the subscription has been established and an initial event message has to be send to the subscriber.

A service manager can implement these concerns in any way imaginable. It has to be thread-safe.

Parameters

<T>	The interface expected by the bound org.fourthline.cling.model.action.ActionExecutors and org.fourthline.cling.model.state.StateVariableAccessors.

Author

Christian Bauer

Member Function Documentation

execute()

void org.fourthline.cling.model.ServiceManager< T >.execute

(

Command< T >

cmd

)

throws Exception

Double-dispatch of arbitrary commands, used by action executors and state variable accessors.

The service manager will execute the given org.fourthline.cling.model.Command and it might decorate the execution, for example, by locking/unlocking access to a shared service implementation before and after the execution.

Parameters

cmd	The command to execute.

Exceptions

Exception

Any exception, without wrapping, as thrown by org.fourthline.cling.model.Command#execute(ServiceManager)

Implemented in org.fourthline.cling.model.DefaultServiceManager< T >.

getCurrentState()

Collection< StateVariableValue > org.fourthline.cling.model.ServiceManager< T >.getCurrentState

(

)

throws Exception

Reading the state of a service manually.

Returns

A Collection of org.fourthline.cling.model.state.StateVariableValue, representing the current state of the service, that is, all evented state variable values.

Exceptions

Exception

Any error that occurred when the service's state was accessed.

Implemented in org.fourthline.cling.model.DefaultServiceManager< T >.

getImplementation()

T org.fourthline.cling.model.ServiceManager< T >.getImplementation

(

)

Returns

An instance with the interface expected by the bound org.fourthline.cling.model.action.ActionExecutors and org.fourthline.cling.model.state.StateVariableAccessors.

Implemented in org.fourthline.cling.model.DefaultServiceManager< T >.

Referenced by org.fourthline.cling.model.action.AbstractActionExecutor.execute().

Here is the caller graph for this function:

getPropertyChangeSupport()

PropertyChangeSupport org.fourthline.cling.model.ServiceManager< T >.getPropertyChangeSupport

(

)

Provides the capability to monitor the service for state changes.

The GENA subsystem expects that this adapter will notify its listeners whenever any evented UPnP state variable of the service has changed its state. The following change event is expected:

• The property name is the constant EVENTED_STATE_VARIABLES.
• The "old value" can be null, only the current state has to be included.
• The "new value" is a Collection of org.fourthline.cling.model.state.StateVariableValue, representing the current state of the service after the change.

The collection has to include values for all state variables, no matter what state variable was updated. Any other event is ignored (e.g. individual property changes).

Returns

An adapter that will notify its listeners whenever any evented state variable changes.

Implemented in org.fourthline.cling.model.DefaultServiceManager< T >.

getService()

LocalService< T > org.fourthline.cling.model.ServiceManager< T >.getService

(

)

Returns

The metadata of the service to which this manager is assigned.

Implemented in org.fourthline.cling.model.DefaultServiceManager< T >.

Member Data Documentation

EVENTED_STATE_VARIABLES

final String org.fourthline.cling.model.ServiceManager< T >.EVENTED_STATE_VARIABLES = "_EventedStateVariables"

static

Use this property name when propagating change events that affect any evented UPnP state variable.

This name is detected by the GENA subsystem.

Referenced by org.fourthline.cling.model.gena.LocalGENASubscription.propertyChange().

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The documentation for this interface was generated from the following file:

• /github/workspace/yaacc/src/main/java/org/fourthline/cling/model/ServiceManager.java