org.springframework.remoting.rmi
Class RmiClientInterceptor

java.lang.Object
  extended by org.springframework.remoting.support.RemotingSupport
      extended by org.springframework.remoting.support.RemoteAccessor
          extended by org.springframework.remoting.support.UrlBasedRemoteAccessor
              extended by org.springframework.remoting.support.RemoteInvocationBasedAccessor
                  extended by org.springframework.remoting.rmi.RmiClientInterceptor
All Implemented Interfaces:
org.aopalliance.aop.Advice, org.aopalliance.intercept.Interceptor, org.aopalliance.intercept.MethodInterceptor, BeanClassLoaderAware, InitializingBean
Direct Known Subclasses:
RmiProxyFactoryBean

public class RmiClientInterceptor
extends RemoteInvocationBasedAccessor
implements org.aopalliance.intercept.MethodInterceptor

MethodInterceptor for accessing conventional RMI services or RMI invokers. The service URL must be a valid RMI URL (e.g. "rmi://localhost:1099/myservice").

RMI invokers work at 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. Spring's unchecked RemoteAccessException will be thrown on remote invocation failure. Of course, in and out parameters have to be serializable.

With conventional RMI services, this invoker is typically used with the RMI service interface. Alternatively, this invoker can also proxy a remote RMI service with a matching non-RMI business interface, i.e. an interface that mirrors the RMI service methods but does not declare RemoteExceptions. In the latter case, RemoteExceptions thrown by the RMI stub will automatically get converted to Spring's unchecked RemoteAccessException.

Since:
29.09.2003
Author:
Juergen Hoeller
See Also:
RmiServiceExporter, RmiProxyFactoryBean, RmiInvocationHandler, RemoteAccessException, RemoteException, Remote

Field Summary
 
Fields inherited from class org.springframework.remoting.support.RemotingSupport
logger
 
Constructor Summary
RmiClientInterceptor()
           
 
Method Summary
 void afterPropertiesSet()
          Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
protected  java.lang.Object doInvoke(org.aopalliance.intercept.MethodInvocation invocation, java.rmi.Remote stub)
          Perform the given invocation on the given RMI stub.
protected  java.lang.Object doInvoke(org.aopalliance.intercept.MethodInvocation methodInvocation, RmiInvocationHandler invocationHandler)
          Apply the given AOP method invocation to the given RmiInvocationHandler.
protected  java.rmi.Remote getStub()
          Return the RMI stub to use.
 java.lang.Object invoke(org.aopalliance.intercept.MethodInvocation invocation)
          Fetches an RMI stub and delegates to doInvoke.
protected  boolean isConnectFailure(java.rmi.RemoteException ex)
          Determine whether the given RMI exception indicates a connect failure.
protected  java.rmi.Remote lookupStub()
          Create the RMI stub, typically by looking it up.
 void prepare()
          Fetches RMI stub on startup, if necessary.
protected  java.lang.Object refreshAndRetry(org.aopalliance.intercept.MethodInvocation invocation)
          Refresh the RMI stub and retry the given invocation.
 void setCacheStub(boolean cacheStub)
          Set whether to cache the RMI stub once it has been located.
 void setLookupStubOnStartup(boolean lookupStubOnStartup)
          Set whether to look up the RMI stub on startup.
 void setRefreshStubOnConnectFailure(boolean refreshStubOnConnectFailure)
          Set whether to refresh the RMI stub on connect failure.
 void setRegistryClientSocketFactory(java.rmi.server.RMIClientSocketFactory registryClientSocketFactory)
          Set a custom RMI client socket factory to use for accessing the RMI registry.
 
Methods inherited from class org.springframework.remoting.support.RemoteInvocationBasedAccessor
createRemoteInvocation, getRemoteInvocationFactory, recreateRemoteInvocationResult, setRemoteInvocationFactory
 
Methods inherited from class org.springframework.remoting.support.UrlBasedRemoteAccessor
getServiceUrl, setServiceUrl
 
Methods inherited from class org.springframework.remoting.support.RemoteAccessor
getServiceInterface, 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
 

Constructor Detail

RmiClientInterceptor

public RmiClientInterceptor()
Method Detail

setLookupStubOnStartup

public void setLookupStubOnStartup(boolean lookupStubOnStartup)
Set whether to look up the RMI stub on startup. Default is "true".

Can be turned off to allow for late start of the RMI server. In this case, the RMI stub will be fetched on first access.

See Also:
setCacheStub(boolean)

setCacheStub

public void setCacheStub(boolean cacheStub)
Set whether to cache the RMI stub once it has been located. Default is "true".

Can be turned off to allow for hot restart of the RMI server. In this case, the RMI stub will be fetched for each invocation.

See Also:
setLookupStubOnStartup(boolean)

setRefreshStubOnConnectFailure

public void setRefreshStubOnConnectFailure(boolean refreshStubOnConnectFailure)
Set whether to refresh the RMI stub on connect failure. Default is "false".

Can be turned on to allow for hot restart of the RMI server. If a cached RMI stub throws an RMI exception that indicates a remote connect failure, a fresh proxy will be fetched and the invocation will be retried.

See Also:
ConnectException, ConnectIOException, NoSuchObjectException

setRegistryClientSocketFactory

public void setRegistryClientSocketFactory(java.rmi.server.RMIClientSocketFactory registryClientSocketFactory)
Set a custom RMI client socket factory to use for accessing the RMI registry.

See Also:
RMIClientSocketFactory, LocateRegistry.getRegistry(String, int, RMIClientSocketFactory)

afterPropertiesSet

public void afterPropertiesSet()
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
Overrides:
afterPropertiesSet in class UrlBasedRemoteAccessor

prepare

public void prepare()
             throws RemoteLookupFailureException
Fetches RMI stub on startup, if necessary.

Throws:
RemoteLookupFailureException - if RMI stub creation failed
See Also:
setLookupStubOnStartup(boolean), lookupStub()

lookupStub

protected java.rmi.Remote lookupStub()
                              throws RemoteLookupFailureException
Create the RMI stub, typically by looking it up.

Called on interceptor initialization if "cacheStub" is "true"; else called for each invocation by getStub().

The default implementation looks up the service URL via java.rmi.Naming. This can be overridden in subclasses.

Returns:
the RMI stub to store in this interceptor
Throws:
RemoteLookupFailureException - if RMI stub creation failed
See Also:
setCacheStub(boolean), Naming.lookup(java.lang.String)

getStub

protected java.rmi.Remote getStub()
                           throws RemoteLookupFailureException
Return the RMI stub to use. Called for each invocation.

The default implementation returns the stub created on initialization, if any. Else, it invokes lookupStub() to get a new stub for each invocation. This can be overridden in subclasses, for example in order to cache a stub for a given amount of time before recreating it, or to test the stub whether it is still alive.

Returns:
the RMI stub to use for an invocation
Throws:
RemoteLookupFailureException - if RMI stub creation failed
See Also:
lookupStub()

invoke

public java.lang.Object invoke(org.aopalliance.intercept.MethodInvocation invocation)
                        throws java.lang.Throwable
Fetches an RMI stub and delegates to doInvoke. If configured to refresh on connect failure, it will call refreshAndRetry(org.aopalliance.intercept.MethodInvocation) on corresponding RMI exceptions.

Specified by:
invoke in interface org.aopalliance.intercept.MethodInterceptor
Throws:
java.lang.Throwable
See Also:
getStub(), doInvoke(MethodInvocation, Remote), refreshAndRetry(org.aopalliance.intercept.MethodInvocation), ConnectException, ConnectIOException, NoSuchObjectException

isConnectFailure

protected boolean isConnectFailure(java.rmi.RemoteException ex)
Determine whether the given RMI exception indicates a connect failure.

The default implementation delegates to RmiClientInterceptorUtils.isConnectFailure(java.rmi.RemoteException).

Parameters:
ex - the RMI exception to check
Returns:
whether the exception should be treated as connect failure

refreshAndRetry

protected java.lang.Object refreshAndRetry(org.aopalliance.intercept.MethodInvocation invocation)
                                    throws java.lang.Throwable
Refresh the RMI stub and retry the given invocation. Called by invoke on connect failure.

Parameters:
invocation - the AOP method invocation
Returns:
the invocation result, if any
Throws:
java.lang.Throwable - in case of invocation failure
See Also:
invoke(org.aopalliance.intercept.MethodInvocation)

doInvoke

protected java.lang.Object doInvoke(org.aopalliance.intercept.MethodInvocation invocation,
                                    java.rmi.Remote stub)
                             throws java.lang.Throwable
Perform the given invocation on the given RMI stub.

Parameters:
invocation - the AOP method invocation
stub - the RMI stub to invoke
Returns:
the invocation result, if any
Throws:
java.lang.Throwable - in case of invocation failure

doInvoke

protected java.lang.Object doInvoke(org.aopalliance.intercept.MethodInvocation methodInvocation,
                                    RmiInvocationHandler invocationHandler)
                             throws java.rmi.RemoteException,
                                    java.lang.NoSuchMethodException,
                                    java.lang.IllegalAccessException,
                                    java.lang.reflect.InvocationTargetException
Apply the given AOP method invocation to the given RmiInvocationHandler.

The default implementation delegates to RemoteInvocationBasedAccessor.createRemoteInvocation(org.aopalliance.intercept.MethodInvocation).

Parameters:
methodInvocation - the current AOP method invocation
invocationHandler - the RmiInvocationHandler to apply the invocation to
Returns:
the invocation result
Throws:
java.rmi.RemoteException - in case of communication errors
java.lang.NoSuchMethodException - if the method name could not be resolved
java.lang.IllegalAccessException - if the method could not be accessed
java.lang.reflect.InvocationTargetException - if the method invocation resulted in an exception
See Also:
RemoteInvocation