org.springframework.remoting.rmi

Class RmiServiceExporter

java.lang.Object

org.springframework.remoting.support.RemotingSupport

org.springframework.remoting.support.RemoteExporter

org.springframework.remoting.support.RemoteInvocationBasedExporter

org.springframework.remoting.rmi.RmiBasedExporter

org.springframework.remoting.rmi.RmiServiceExporter

All Implemented Interfaces:

Aware, BeanClassLoaderAware, DisposableBean, InitializingBean

public class RmiServiceExporter
extends RmiBasedExporter
implements InitializingBean, DisposableBean

RMI exporter that exposes the specified service as RMI object with the specified name. Such services can be accessed via plain RMI or via RmiProxyFactoryBean. Also supports exposing any non-RMI service via RMI invokers, to be accessed via RmiClientInterceptor / RmiProxyFactoryBean's automatic detection of such invokers.

With an RMI invoker, RMI communication works on the RmiInvocationHandler level, needing only one stub for any service. Service interfaces do not have to extend java.rmi.Remote or throw java.rmi.RemoteException on all methods, but in and out parameters have to be serializable.

The major advantage of RMI, compared to Hessian and Burlap, is serialization. Effectively, any serializable Java object can be transported without hassle. Hessian and Burlap have their own (de-)serialization mechanisms, but are HTTP-based and thus much easier to setup than RMI. Alternatively, consider Spring's HTTP invoker to combine Java serialization with HTTP-based transport.

Note: RMI makes a best-effort attempt to obtain the fully qualified host name. If one cannot be determined, it will fall back and use the IP address. Depending on your network configuration, in some cases it will resolve the IP to the loopback address. To ensure that RMI will use the host name bound to the correct network interface, you should pass the java.rmi.server.hostname property to the JVM that will export the registry and/or the service using the "-D" JVM argument. For example: -Djava.rmi.server.hostname=myserver.com

Since:

13.05.2003

Author:

Juergen Hoeller

See Also:

RmiClientInterceptor, RmiProxyFactoryBean, Remote, RemoteException, HessianServiceExporter, BurlapServiceExporter, HttpInvokerServiceExporter

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	alwaysCreateRegistry
private java.rmi.server.RMIClientSocketFactory	clientSocketFactory
private boolean	createdRegistry
private java.rmi.Remote	exportedObject
private java.rmi.registry.Registry	registry
private java.rmi.server.RMIClientSocketFactory	registryClientSocketFactory
private java.lang.String	registryHost
private int	registryPort
private java.rmi.server.RMIServerSocketFactory	registryServerSocketFactory
private boolean	replaceExistingBinding
private java.rmi.server.RMIServerSocketFactory	serverSocketFactory
private java.lang.String	serviceName
private int	servicePort

Fields inherited from class org.springframework.remoting.support.RemotingSupport

logger

Constructor Summary

Constructors

Constructor and Description
RmiServiceExporter()

Method Summary

Modifier and Type	Method and Description
void	afterPropertiesSet() Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
void	destroy() Unbind the RMI service from the registry on bean factory shutdown.
protected java.rmi.registry.Registry	getRegistry(int registryPort) Locate or create the RMI registry for this exporter.
protected java.rmi.registry.Registry	getRegistry(int registryPort, java.rmi.server.RMIClientSocketFactory clientSocketFactory, java.rmi.server.RMIServerSocketFactory serverSocketFactory) Locate or create the RMI registry for this exporter.
protected java.rmi.registry.Registry	getRegistry(java.lang.String registryHost, int registryPort, java.rmi.server.RMIClientSocketFactory clientSocketFactory, java.rmi.server.RMIServerSocketFactory serverSocketFactory) Locate or create the RMI registry for this exporter.
void	prepare() Initialize this service exporter, registering the service as RMI object.
void	setAlwaysCreateRegistry(boolean alwaysCreateRegistry) Set whether to always create the registry in-process, not attempting to locate an existing registry at the specified port.
void	setClientSocketFactory(java.rmi.server.RMIClientSocketFactory clientSocketFactory) Set a custom RMI client socket factory to use for exporting the service.
void	setRegistry(java.rmi.registry.Registry registry) Specify the RMI registry to register the exported service with.
void	setRegistryClientSocketFactory(java.rmi.server.RMIClientSocketFactory registryClientSocketFactory) Set a custom RMI client socket factory to use for the RMI registry.
void	setRegistryHost(java.lang.String registryHost) Set the host of the registry for the exported RMI service, i.e.
void	setRegistryPort(int registryPort) Set the port of the registry for the exported RMI service, i.e.
void	setRegistryServerSocketFactory(java.rmi.server.RMIServerSocketFactory registryServerSocketFactory) Set a custom RMI server socket factory to use for the RMI registry.
void	setReplaceExistingBinding(boolean replaceExistingBinding) Set whether to replace an existing binding in the RMI registry, that is, whether to simply override an existing binding with the specified service in case of a naming conflict in the registry.
void	setServerSocketFactory(java.rmi.server.RMIServerSocketFactory serverSocketFactory) Set a custom RMI server socket factory to use for exporting the service.
void	setServiceName(java.lang.String serviceName) Set the name of the exported RMI service, i.e.
void	setServicePort(int servicePort) Set the port that the exported RMI service will use.
protected void	testRegistry(java.rmi.registry.Registry registry) Test the given RMI registry, calling some operation on it to check whether it is still active.
private void	unexportObjectSilently() Unexport the registered RMI object, logging any exception that arises.

Methods inherited from class org.springframework.remoting.rmi.RmiBasedExporter

getObjectToExport, invoke

Methods inherited from class org.springframework.remoting.support.RemoteInvocationBasedExporter

getRemoteInvocationExecutor, invokeAndCreateResult, setRemoteInvocationExecutor

Methods inherited from class org.springframework.remoting.support.RemoteExporter

checkService, checkServiceInterface, getExporterName, getProxyForService, getService, getServiceInterface, setInterceptors, setRegisterTraceInterceptor, setService, setServiceInterface

Methods inherited from class org.springframework.remoting.support.RemotingSupport

getBeanClassLoader, overrideThreadContextClassLoader, resetThreadContextClassLoader, setBeanClassLoader

Methods inherited from class java.lang.Object

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

Field Detail

serviceName

private java.lang.String serviceName

servicePort

private int servicePort

clientSocketFactory

private java.rmi.server.RMIClientSocketFactory clientSocketFactory

serverSocketFactory

private java.rmi.server.RMIServerSocketFactory serverSocketFactory

registry

private java.rmi.registry.Registry registry

registryHost

private java.lang.String registryHost

registryPort

private int registryPort

registryClientSocketFactory

private java.rmi.server.RMIClientSocketFactory registryClientSocketFactory

registryServerSocketFactory

private java.rmi.server.RMIServerSocketFactory registryServerSocketFactory

alwaysCreateRegistry

private boolean alwaysCreateRegistry

replaceExistingBinding

private boolean replaceExistingBinding

exportedObject

private java.rmi.Remote exportedObject

createdRegistry

private boolean createdRegistry

Constructor Detail

RmiServiceExporter

public RmiServiceExporter()

Method Detail

setServiceName

public void setServiceName(java.lang.String serviceName)

Set the name of the exported RMI service, i.e. rmi://host:port/NAME

setServicePort

public void setServicePort(int servicePort)

Set the port that the exported RMI service will use.

Default is 0 (anonymous port).

setClientSocketFactory

public void setClientSocketFactory(java.rmi.server.RMIClientSocketFactory clientSocketFactory)

Set a custom RMI client socket factory to use for exporting the service.

If the given object also implements java.rmi.server.RMIServerSocketFactory, it will automatically be registered as server socket factory too.

See Also:

setServerSocketFactory(java.rmi.server.RMIServerSocketFactory), RMIClientSocketFactory, RMIServerSocketFactory, UnicastRemoteObject.exportObject(Remote, int, RMIClientSocketFactory, RMIServerSocketFactory)

setServerSocketFactory

public void setServerSocketFactory(java.rmi.server.RMIServerSocketFactory serverSocketFactory)

Set a custom RMI server socket factory to use for exporting the service.

Only needs to be specified when the client socket factory does not implement java.rmi.server.RMIServerSocketFactory already.

See Also:

setClientSocketFactory(java.rmi.server.RMIClientSocketFactory), RMIClientSocketFactory, RMIServerSocketFactory, UnicastRemoteObject.exportObject(Remote, int, RMIClientSocketFactory, RMIServerSocketFactory)

setRegistry

public void setRegistry(java.rmi.registry.Registry registry)

Specify the RMI registry to register the exported service with. Typically used in combination with RmiRegistryFactoryBean.

Alternatively, you can specify all registry properties locally. This exporter will then try to locate the specified registry, automatically creating a new local one if appropriate.

Default is a local registry at the default port (1099), created on the fly if necessary.

See Also:

RmiRegistryFactoryBean, setRegistryHost(java.lang.String), setRegistryPort(int), setRegistryClientSocketFactory(java.rmi.server.RMIClientSocketFactory), setRegistryServerSocketFactory(java.rmi.server.RMIServerSocketFactory)

setRegistryHost

public void setRegistryHost(java.lang.String registryHost)

Set the host of the registry for the exported RMI service, i.e. rmi://HOST:port/name

Default is localhost.

setRegistryPort

public void setRegistryPort(int registryPort)

Set the port of the registry for the exported RMI service, i.e. rmi://host:PORT/name

Default is Registry.REGISTRY_PORT (1099).

See Also:

Registry.REGISTRY_PORT

setRegistryClientSocketFactory

public void setRegistryClientSocketFactory(java.rmi.server.RMIClientSocketFactory registryClientSocketFactory)

Set a custom RMI client socket factory to use for the RMI registry.

If the given object also implements java.rmi.server.RMIServerSocketFactory, it will automatically be registered as server socket factory too.

See Also:

setRegistryServerSocketFactory(java.rmi.server.RMIServerSocketFactory), RMIClientSocketFactory, RMIServerSocketFactory, LocateRegistry.getRegistry(String, int, RMIClientSocketFactory)

setRegistryServerSocketFactory

public void setRegistryServerSocketFactory(java.rmi.server.RMIServerSocketFactory registryServerSocketFactory)

Set a custom RMI server socket factory to use for the RMI registry.

Only needs to be specified when the client socket factory does not implement java.rmi.server.RMIServerSocketFactory already.

See Also:

setRegistryClientSocketFactory(java.rmi.server.RMIClientSocketFactory), RMIClientSocketFactory, RMIServerSocketFactory, LocateRegistry.createRegistry(int, RMIClientSocketFactory, RMIServerSocketFactory)

setAlwaysCreateRegistry

public void setAlwaysCreateRegistry(boolean alwaysCreateRegistry)

Set whether to always create the registry in-process, not attempting to locate an existing registry at the specified port.

Default is "false". Switch this flag to "true" in order to avoid the overhead of locating an existing registry when you always intend to create a new registry in any case.

setReplaceExistingBinding

public void setReplaceExistingBinding(boolean replaceExistingBinding)

Set whether to replace an existing binding in the RMI registry, that is, whether to simply override an existing binding with the specified service in case of a naming conflict in the registry.

Default is "true", assuming that an existing binding for this exporter's service name is an accidental leftover from a previous execution. Switch this to "false" to make the exporter fail in such a scenario, indicating that there was already an RMI object bound.

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.rmi.RemoteException

Description copied from interface: InitializingBean

Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).

This method allows the bean instance to perform initialization only possible when all bean properties have been set and to throw an exception in the event of misconfiguration.

Specified by:

afterPropertiesSet in interface InitializingBean

Throws:

java.rmi.RemoteException

prepare

public void prepare()
             throws java.rmi.RemoteException

Initialize this service exporter, registering the service as RMI object.

Creates an RMI registry on the specified port if none exists.

Throws:

java.rmi.RemoteException - if service registration failed

getRegistry

protected java.rmi.registry.Registry getRegistry(java.lang.String registryHost,
                                                 int registryPort,
                                                 java.rmi.server.RMIClientSocketFactory clientSocketFactory,
                                                 java.rmi.server.RMIServerSocketFactory serverSocketFactory)
                                          throws java.rmi.RemoteException

Locate or create the RMI registry for this exporter.

Parameters:

registryHost - the registry host to use (if this is specified, no implicit creation of a RMI registry will happen)

registryPort - the registry port to use

clientSocketFactory - the RMI client socket factory for the registry (if any)

serverSocketFactory - the RMI server socket factory for the registry (if any)

Returns:

the RMI registry

Throws:

java.rmi.RemoteException - if the registry couldn't be located or created

getRegistry

protected java.rmi.registry.Registry getRegistry(int registryPort,
                                                 java.rmi.server.RMIClientSocketFactory clientSocketFactory,
                                                 java.rmi.server.RMIServerSocketFactory serverSocketFactory)
                                          throws java.rmi.RemoteException

Locate or create the RMI registry for this exporter.

Parameters:

registryPort - the registry port to use

clientSocketFactory - the RMI client socket factory for the registry (if any)

serverSocketFactory - the RMI server socket factory for the registry (if any)

Returns:

the RMI registry

Throws:

java.rmi.RemoteException - if the registry couldn't be located or created

getRegistry

protected java.rmi.registry.Registry getRegistry(int registryPort)
                                          throws java.rmi.RemoteException

Locate or create the RMI registry for this exporter.

Parameters:

registryPort - the registry port to use

Returns:

the RMI registry

Throws:

java.rmi.RemoteException - if the registry couldn't be located or created

testRegistry

protected void testRegistry(java.rmi.registry.Registry registry)
                     throws java.rmi.RemoteException

Test the given RMI registry, calling some operation on it to check whether it is still active.

Default implementation calls Registry.list().

Parameters:

registry - the RMI registry to test

Throws:

java.rmi.RemoteException - if thrown by registry methods

See Also:

Registry.list()

destroy

public void destroy()
             throws java.rmi.RemoteException

Unbind the RMI service from the registry on bean factory shutdown.

Specified by:

destroy in interface DisposableBean

Throws:

java.rmi.RemoteException

unexportObjectSilently

private void unexportObjectSilently()

Unexport the registered RMI object, logging any exception that arises.