org.apache.river.phoenix

Class ActivationGroupImpl

java.lang.Object

java.rmi.server.RemoteObject

java.rmi.server.RemoteServer

java.rmi.server.UnicastRemoteObject

java.rmi.activation.ActivationGroup

net.jini.activation.ActivationGroup

org.apache.river.phoenix.AbstractActivationGroup

org.apache.river.phoenix.ActivationGroupImpl

All Implemented Interfaces:

Serializable, ActivationInstantiator, Remote, ServerProxyTrust

public class ActivationGroupImpl
extends AbstractActivationGroup

The default activation group implementation for phoenix. Instances of this class are configurable through a Configuration, as detailed further below, and provide the necessary support to allow exporter-based remote objects to go inactive. Instances of this class support the creation of remote objects through the normal activatable constructor; an activatable remote object must either implement the ProxyAccessor interface to return a suitable proxy for the remote object, or the remote object must itself be serializable and marshalling the object must produce a suitable proxy for the remote object.

An instance of this class can be configured by specifying an ActivationGroupData instance containing configuration options as the initialization data for the activation group. Typically this is accomplished indirectly, by setting the groupConfig configuration entry for phoenix itself. The following entries are obtained from the configuration, all for the component named org.apache.river.phoenix:

•	loginContext
	Type:	LoginContext
	Default:	null
	Description:	JAAS login context

•	inheritGroupSubject
	Type:	boolean
	Default:	false
	Description:	if true, group subject is inherited when an activatable object is created

•	instantiatorExporter
	Type:	Exporter
	Default:	retains existing JRMP export of instantiator
	Description:	ActivationInstantiator exporter

•	monitorPreparer
	Type:	ProxyPreparer
	Default:	new BasicProxyPreparer()
	Description:	ActivationMonitor proxy preparer

•	systemPreparer
	Type:	ProxyPreparer
	Default:	new BasicProxyPreparer()
	Description:	ActivationSystem proxy preparer

•	unexportTimeout
	Type:	int
	Default:	60000
	Description:	maximum time in milliseconds to wait for in-progress calls to finish before forcibly unexporting the group when going inactive

•	unexportWait
	Type:	int
	Default:	10
	Description:	milliseconds to wait between unexport attempts when going inactive

This class depends on its createGroup method being called to initialize the activation group. As such, this class cannot be used in conjunction with the standard rmid.

Since:

2.0

Author:

Sun Microsystems, Inc.

See Also:

Serialized Form

Field Summary

Fields inherited from class java.rmi.server.RemoteObject

ref

Constructor Summary

Constructors

Constructor and Description
ActivationGroupImpl(ActivationGroupID id, MarshalledObject data) Creates an instance with the specified group identifier and initialization data.

Method Summary

Modifier and Type	Method and Description
static ActivationGroup	createGroup(ActivationGroupID id, ActivationGroupDesc desc, long incarnation) Creates an ActivationGroup instance and returns it.

Methods inherited from class org.apache.river.phoenix.AbstractActivationGroup

activeObject, export, getProxyVerifier, inactiveObject, inactiveObject, newInstance, writeReplace

Methods inherited from class net.jini.activation.ActivationGroup

inactive

Methods inherited from class java.rmi.activation.ActivationGroup

activeObject, currentGroupID, getSystem, inactiveGroup, setSystem

Methods inherited from class java.rmi.server.UnicastRemoteObject

clone, exportObject, exportObject, exportObject, unexportObject

Methods inherited from class java.rmi.server.RemoteServer

getClientHost, getLog, setLog

Methods inherited from class java.rmi.server.RemoteObject

equals, getRef, hashCode, toString, toStub

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ActivationGroupImpl

public ActivationGroupImpl(ActivationGroupID id,
                           MarshalledObject data)
                    throws ActivationException,
                           RemoteException

Creates an instance with the specified group identifier and initialization data. This constructor must be called indirectly, via createGroup. By default, this instance automatically exports itself as a UnicastRemoteObject. (This is a limitation of the existing activation system design.) If an Exporter was obtained by createGroup, then this instance is unexported from the JRMP runtime and re-exported using that exporter. (Any incoming remote calls received on the original JRMP export before this instance can be unexported will be refused with a security exception thrown.) The activeGroup method of the activation system proxy (in the group identifier) is called to make the group active. The returned ActivationMonitor proxy is passed to the corresponding ProxyPreparer obtained by createGroup. Note that after this constructor returns, ActivationGroup.createGroup will also call activeGroup (so the activation system must accept idempotent calls to that method), but the ActivationMonitor proxy returned by that call will not be used.

Parameters:

id - the activation group identifier

data - group initialization data (ignored)

Throws:

RemoteException - if the group could not be exported or made active, or proxy preparation fails

ActivationException - if the constructor was not called indirectly from createGroup

Method Detail

createGroup

public static ActivationGroup createGroup(ActivationGroupID id,
                                          ActivationGroupDesc desc,
                                          long incarnation)
                                   throws ActivationException

Creates an ActivationGroup instance and returns it. An ActivationGroupData instance is extracted from the initialization data, and a Configuration is obtained by calling Configuration.Provider.getInstance with the configuration options from that instance. A LoginContext is obtained from the loginContext configuration entry, if one exists; if the value is not null, a login is performed on that context, and the resulting Subject (set to be read-only) is used as the subject when executing the rest of this method. The subject is also used for all subsequent remote calls by this class to the ActivationMonitor. The ActivationSystem proxy (obtained from the ActivationGroupID) is passed to the ProxyPreparer given by the systemPreparer configuration entry, if one exists; a new ActivationGroupID is constructed with the resulting proxy. An Exporter instance is obtained from the instantiatorExporter configuration entry, if one exists; this exporter will be used (in the constructor of this class) to export the group. A ProxyPreparer instance is obtained from the monitorPreparer configuration entry, if one exists; this preparer will be used (in the constructor of this class) to prepare the ActivationMonitor. A call is then made to ActivationGroup.createGroup with the new group identifier, the activation group descriptor, and the group incarnation number, and the result of that call is returned.

Parameters:

id - the activation group identifier

desc - the activation group descriptor

incarnation - the group's incarnation number (zero on initial creation)

Returns:

the created activation group

Throws:

ActivationException - if a group already exists or if an exception occurs during group creation