Rio Project 4.2 API Documentation

org.rioproject.boot
Class RioActivatableServiceDescriptor

java.lang.Object
  org.rioproject.boot.RioServiceDescriptor
      org.rioproject.boot.RioActivatableServiceDescriptor

All Implemented Interfaces:

ServiceDescriptor

public class RioActivatableServiceDescriptor
extends RioServiceDescriptor

Class used to launch shared, activatable services. Clients construct this object with the details of the service to be launched, then call create to launch the service in the activation system group identified by the sharedGroupLog constructor parameter.

This class depends on ActivateWrapper to provide separation of the import codebase (where the server classes are loaded from) from the export codebase (where clients should load classes from for stubs,etc.) as well as providing an independent security policy file for each service object. This functionality allows multiple service objects to be placed in the same activation system group, with each object maintaining a distinct codebase and policy.

Services need to implement the constructor required by ActivateWrapper. The following items are discussed below:

• Configuring RioActivatableServiceDescriptor
• Logging

Configuring RioActivatableServiceDescriptor

This implementation of RioActivatableServiceDescriptor supports the following configuration entries, with component org.rioproject.boot:

•	activationIdPreparer
	Type:	ProxyPreparer
	Default:	new BasicProxyPreparer()
	Description:	The proxy preparer for the service's activation ID. The value should not be null. This class calls the ActivationID.activate(boolean) method on instances of ActivationID when they need to re/activate the service.

•	activationSystemPreparer
	Type:	ProxyPreparer
	Default:	new BasicProxyPreparer()
	Description:	The proxy preparer for the proxy for the activation system. The value should not be null. The service starter calls the unregisterObject method on the java.rmi.activation.ActivationSystem when there is a problem creating a service.

Loggers and Logging Levels

The implementation uses the java.util.logging.Logger, named org.rioproject.boot. The following table describes the type of information logged as well as the levels of information logged.

org.rioproject.boot

Level	Description
FINER	for high level service operation tracing
FINEST	for low level service operation tracing

Author:

Dennis Reedy

Nested Class Summary

static class

RioActivatableServiceDescriptor.Created Object returned by RioActivatableServiceDescriptor.create() method that returns the proxy, group identifier, and activation identifier for the created service.

Constructor Summary

RioActivatableServiceDescriptor(String codebase, String policy, String classpath, String implClassName, String sharedGroupLog, String[] serverConfigArgs, boolean restart)
Create a RioActivatableServiceDescriptor, calling the other overloaded constructor with the host and port parameters set to null and 0, respectively.

RioActivatableServiceDescriptor(String codebase, String policy, String classpath, String implClassName, String sharedGroupLog, String[] serverConfigArgs, boolean restart, String host, int port)
Create a RioActivatableServiceDescriptor, assigning given parameters to their associated, internal fields.

Method Summary

Object	create(Configuration config) Method that attempts to create a service based on the service description information provided via constructor parameters.
String	getActivationSystemHost() Activation system host accessor method.
int	getActivationSystemPort() Activation system port accessor method.
boolean	getRestart() Restart accessor method.
String	getSharedGroupLog() Shared group log accessor method.
String	toString()

Methods inherited from class org.rioproject.boot.RioServiceDescriptor

getClasspath, getCodebase, getImplClassName, getLifeCycle, getPolicy, getServerConfigArgs

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RioActivatableServiceDescriptor

public RioActivatableServiceDescriptor(String codebase,
                                       String policy,
                                       String classpath,
                                       String implClassName,
                                       String sharedGroupLog,
                                       String[] serverConfigArgs,
                                       boolean restart)

Create a RioActivatableServiceDescriptor, calling the other overloaded constructor with the host and port parameters set to null and 0, respectively.

Parameters:

codebase - location where clients can download required service-related classes (for example, stubs, proxies, etc.). Codebase components must be separated by spaces in which each component is in URL format.

policy - server policy filename or URL

classpath - location where server implementation classes can be found. Classpath components must be separated by path separators.

implClassName - name of server implementation class

sharedGroupLog - The name of the log

serverConfigArgs - service configuration arguments

restart - boolean flag passed through as the restart parameter to the ActivationDesc constructor used to register the service with the activation system.

RioActivatableServiceDescriptor

public RioActivatableServiceDescriptor(String codebase,
                                       String policy,
                                       String classpath,
                                       String implClassName,
                                       String sharedGroupLog,
                                       String[] serverConfigArgs,
                                       boolean restart,
                                       String host,
                                       int port)

Create a RioActivatableServiceDescriptor, assigning given parameters to their associated, internal fields.

Parameters:

codebase - location where clients can download required service-related classes (for example, stubs, proxies, etc.). Codebase components must be separated by spaces in which each component is in URL format.

policy - server policy filename or URL

classpath - location where server implementation classes can be found. Classpath components must be separated by path separators.

implClassName - name of server implementation class

sharedGroupLog - The name of the log

serverConfigArgs - service configuration arguments

restart - boolean flag passed through as the restart parameter to the ActivationDesc constructor used to register the service with the activation system.

host - hostname of desired activation system. If null, defaults to the localhost.

port - port of desired activation system. If value is <= 0, then defaults to ActivationSystem.SYSTEM_PORT.

Method Detail

getSharedGroupLog

public final String getSharedGroupLog()

Shared group log accessor method.

Returns:

The Shared group log associated with this service descriptor.

getRestart

public final boolean getRestart()

Restart accessor method.

Returns:

The restart mode associated with this service descriptor.

getActivationSystemHost

public final String getActivationSystemHost()

Activation system host accessor method.

Returns:

The activation system host associated with this service descriptor.

getActivationSystemPort

public final int getActivationSystemPort()

Activation system port accessor method.

Returns:

The activation system port associated with this service descriptor.

create

public Object create(Configuration config)
              throws Exception

Method that attempts to create a service based on the service description information provided via constructor parameters.

This method:

• creates an ActivateWrapper.ActivateDesc with the provided constructor parameter information
• retrieves the java.rmi.activation.ActivationGroupID group identifie} associated with the provided shared group log.
• invokes ActivateWrapper.register()with the provided information.
• obtains an "inner" proxy by calling ActivationID#activate(true) on the object returned from ActivateWrapper.register(), which also activates the service instance.
• The service proxy is obtained by calling ServiceProxyAccessor.getServiceProxy() on the "inner" proxy instance. Otherwise, the "inner" proxy reference is used in the return value.

Specified by:

create in interface ServiceDescriptor

Overrides:

create in class RioServiceDescriptor

Returns:

A org.rioproject.boot.RioActivatableServiceDescriptor.Created object that contains the group identifier, activation ID, and proxy associated with the newly created service instance.

Throws:

Exception

See Also:

ServiceDescriptor.create(net.jini.config.Configuration)

toString

public String toString()

Overrides:

toString in class RioServiceDescriptor