|
Generated by JDiff |
||||||||
PREV PACKAGE NEXT PACKAGE FRAMES NO FRAMES |
This file contains all the changes in documentation in the packagejava.rmi.activation
as colored differences. Deletions are shownlike this, and additions are shown like this.
If no deletions or additions are shown in an entry, the HTML tags will be what has changed. The new HTML tags are shown in the differences. If no documentation existed, and then some was added in a later version, this change is noted in the appropriate class pages of differences, but the change is not shown on this page. Only changes in existing text are shown here. Similarly, documentation which was inherited from another class or interface is not shown here.
Note that an HTML error in the new documentation may cause the display of other documentation changes to be presented incorrectly. For instance, failure to close a <code> tag will cause all subsequent paragraphs to be displayed differently.
TheActivatable
class provides support for remote objects that require persistent access over time and that can be activated by the system. @author Ann Wollrath @version 1.30 0131 02/12/03/18 @since 1.2
AnClass ActivationGroup, ActivationSystem getSystem()ActivationGroup
is responsible for creating new instances of "activatable" objects in its group informing itsActivationMonitor
when either: its object's become active or inactive or the group as a whole becomes inactive.An
ActivationGroup
is initially created in one of several ways:
- as a side-effect of creating an
ActivationDesc
without an explicitActivationGroupID
for the first activatable object in the group or- via the
ActivationGroup.createGroup
method- as a side-effect of activating the first object in a group whose
ActivationGroupDesc
was only registered.Only the activator can recreate an
ActivationGroup
. The activator spawns as needed a separate VM (as a child process for example) for each registered activation group and directs activation requests to the appropriate group. It is implementation specific how VMs are spawned. An activation group is created via theActivationGroup.createGroup
static method. ThecreateGroup
method has two requirements on the group to be created: 1) the group must be a concrete subclass ofActivationGroup
and 2) the group must have a constructor that takes two arguments:
- the group's
ActivationGroupID
and- the group's initialization data (in a
java.rmi.MarshalledObject
)When created the default implementation of
ActivationGroup
will override the system properties with the properties requested when itsActivationGroupDesc
was created and will set ajava.rmi.RMISecurityManager
as the default system security manager. If your application requires specific properties to be set when objects are activated in the group the application should create a specialProperties
object containing these properties then create anActivationGroupDesc
with theProperties
object and useActivationGroup.createGroup
before creating anyActivationDesc
s (before the defaultActivationGroupDesc
is created). If your application requires the use of a security manager other thanjava.rmi.RMISecurityManager
in the ActivativationGroupDescriptor properties list you can setjava.security.manager
property to the name of the security manager you would like to install. @author Ann Wollrath @version 1.39 0141 02/1204/0308 @see ActivationInstantiator @see ActivationGroupDesc @see ActivationGroupID @since 1.2
Returns the activation system for the VM. The activation system may be set by theClass ActivationGroup, void setSystem(ActivationSystem)setSystem
method. If the activation system is not set via thesetSystem
method then thegetSystem
method attempts to obtain a reference to theActivationSystem
by looking up the name "java.rmi.activation.ActivationSystem" in the Activator's registry. By default the port number used to look up the activation system is defined byActivationSystem.SYSTEM_PORT
. This port can be overridden by setting the propertyjava.rmi.activation.port
. @return the activation system for the VM/group @exception ActivationException if activation system cannot be obtained or is not bound (means that it is not running) @see #setSystem @since 1.2
Set the activation system for the VM. The activation system can only be set it if no group is currently active. If the activation system is not set via this call then thegetSystem
method attempts to obtain a reference to theActivationSystem
by looking up the name "java.rmi.activation.ActivationSystem" in the Activator's registry. By default the port number used to look up the activation system is defined byActivationSystem.SYSTEM_PORT
. This port can be overridden by setting the propertyjava.rmi.activation.port
.If there is a security manager this method first calls the security manager's
checkSetFactory
method. This could result in a SecurityException. @param system remote reference to theActivationSystem
@exception ActivationException if activation system is already set @exception SecurityException if permission to set the activation system is denied. (Note: The default implementation of the security managercheckSetFactory
method requires the RuntimePermission "setFactory") @see #getSystem @see SecurityManager#checkSetFactory @since 1.2
AnClass ActivationInstantiator, MarshalledObject newInstance(ActivationID, ActivationDesc)ActivationInstantiator
is responsible for creating instances of "activatable" objects. A concrete subclass ofActivationGroup
implements thenewInstance
method to handle creating objects within the group. @author Ann Wollrath @version 1.121312/03/0118/02 @see ActivationGroup @since 1.2
The activator calls an instantiator'snewInstance
method in order to recreate in that group an object with the activation identifierid
and descriptordesc
. The instantiator is responsible for:@param id the object's activation identifier @param desc the object's descriptor @return a marshalled object containing the serialized representation of remote object's stub @exception ActivationException if object activation fails @exception RemoteException if remote call fails @since 1.2
- determining the class for the object using the descriptor's
getClassName
method- loading the class from the code location obtained from the descriptor (using the
getLocation
method)- creating an instance of the class by invoking the special "activation" constructor of the object's class that takes two arguments: the object's
ActivationID
and theMarshalledObject
containing object specific initialization data and- returning a MarshalledObject containing the stub for the remote object it created
TheClass ActivationSystem, ActivationDesc getActivationDesc(ActivationID)ActivationSystem
provides a means for registering groups and "activatable" objects to be activated within those groups. TheActivationSystem
works closely with theActivator
which activates objects registered via theActivationSystem
and theActivationMonitor
which obtains information about active and inactive objects and inactive groups. @author Ann Wollrath @version 1.141512/03/0118/02 @see Activator @see ActivationMonitor @since 1.2
Returns the activation descriptor for the object with the activation identifierClass ActivationSystem, ActivationGroupDesc getActivationGroupDesc(ActivationGroupID)id
. @param id the activation identifier for the activatable object @exception UnknownObjectException ifid
is not registered @exception ActivationException for general failure @exception RemoteException if remote call fails @return the activation descriptor @see #setActivationDesc @since 1.2
Returns the activation group descriptor for the group with the activation group identifierClass ActivationSystem, ActivationDesc setActivationDesc(ActivationID, ActivationDesc)id
. @param id the activation group identifier for the group @exception UnknownGroupException ifid
is not registered @exception ActivationException for general failure @exception RemoteException if remote call fails @return the activation group descriptor @see #setActivationGroupDesc @since 1.2
Set the activation descriptorClass ActivationSystem, ActivationGroupDesc setActivationGroupDesc(ActivationGroupID, ActivationGroupDesc)desc
for the object with the activation identifierid
. The change will take effect upon subsequent activation of the object. @param id the activation identifier for the activatable object @param desc the activation descriptor for the activatable object @exception UnknownGroupException the group associated withdesc
is not a registered group @exception UnknownObjectException the activationid
is not registered @exception ActivationException for general failure (e.g. unable to update log) @exception RemoteException if remote call fails @return the previous value of the activation descriptor @see #getActivationDesc @since 1.2
Set the activation group descriptordesc
for the object with the activation group identifierid
. The change will take effect upon subsequent activation of the group. @param id the activation group identifier for the activation group @param desc the activation group descriptor for the activation group @exception UnknownGroupException the group associated withid
is not a registered group @exception ActivationException for general failure (e.g. unable to update log) @exception RemoteException if remote call fails @return the previous value of the activation group descriptor @see #getActivationGroupDesc @since 1.2