org.springframework.remoting.httpinvoker
Class HttpInvokerClientInterceptor

java.lang.Object
  org.springframework.remoting.support.RemoteAccessor
      org.springframework.remoting.support.UrlBasedRemoteAccessor
          org.springframework.remoting.support.RemoteInvocationBasedAccessor
              org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor

All Implemented Interfaces:

Advice, Interceptor, MethodInterceptor, BeanClassLoaderAware, InitializingBean, HttpInvokerClientConfiguration

Direct Known Subclasses:

HttpInvokerProxyFactoryBean

public class HttpInvokerClientInterceptor
extends RemoteInvocationBasedAccessor
implements MethodInterceptor, HttpInvokerClientConfiguration, BeanClassLoaderAware

Interceptor for accessing an HTTP invoker service. The service URL must be an HTTP URL exposing an HTTP invoker service.

Serializes remote invocation objects and deserializes remote invocation result objects. Uses Java serialization just like RMI, but provides the same ease of setup as Caucho's HTTP-based Hessian and Burlap protocols.

HTTP invoker is a very extensible and customizable protocol. It supports the RemoteInvocationFactory mechanism, like RMI invoker, allowing to include additional invocation attributes (for example, a security context). Furthermore, it allows to customize request execution via the HttpInvokerRequestExecutor strategy.

Can use the JDK's RMIClassLoader to load classes from a given codebase, performing on-demand dynamic code download from a remote location. The codebase can consist of multiple URLs, separated by spaces. Note that RMIClassLoader requires a SecurityManager to be set, analogous to when using dynamic class download with standard RMI! (See the RMI documentation for details.)

Since:

1.1

Author:

Juergen Hoeller

See Also:

UrlBasedRemoteAccessor.setServiceUrl(java.lang.String), setCodebaseUrl(java.lang.String), RemoteInvocationBasedAccessor.setRemoteInvocationFactory(org.springframework.remoting.support.RemoteInvocationFactory), setHttpInvokerRequestExecutor(org.springframework.remoting.httpinvoker.HttpInvokerRequestExecutor), HttpInvokerServiceExporter, HttpInvokerProxyFactoryBean, RMIClassLoader

Field Summary

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

logger

Constructor Summary

HttpInvokerClientInterceptor()

Method Summary

void	afterPropertiesSet() Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
protected RemoteAccessException	convertHttpInvokerAccessException(Throwable ex) Convert the given HTTP invoker access exception to an appropriate Spring RemoteAccessException.
protected RemoteInvocationResult	executeRequest(RemoteInvocation invocation) Execute the given remote invocation via the HttpInvokerRequestExecutor.
protected ClassLoader	getBeanClassLoader() Return the ClassLoader that this accessor operates in, to be used for deserializing and for generating proxies.
String	getCodebaseUrl() Return the codebase URL to download classes from if not found locally.
HttpInvokerRequestExecutor	getHttpInvokerRequestExecutor() Return the HttpInvokerRequestExecutor used by this remote accessor.
Object	invoke(MethodInvocation methodInvocation)
void	setBeanClassLoader(ClassLoader classLoader) Callback that supplies the bean class loader to a bean instance.
void	setCodebaseUrl(String codebaseUrl) Set the codebase URL to download classes from if not found locally.
void	setHttpInvokerRequestExecutor(HttpInvokerRequestExecutor httpInvokerRequestExecutor) Set the HttpInvokerRequestExecutor implementation to use for executing remote invocations.

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 java.lang.Object

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

Methods inherited from interface org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration

getServiceUrl

Constructor Detail

HttpInvokerClientInterceptor

public HttpInvokerClientInterceptor()

Method Detail

setCodebaseUrl

public void setCodebaseUrl(String codebaseUrl)

Set the codebase URL to download classes from if not found locally. Can consists of multiple URLs, separated by spaces.

Follows RMI's codebase conventions for dynamic class download. In contrast to RMI, where the server determines the URL for class download (via the "java.rmi.server.codebase" system property), it's the client that determines the codebase URL here. The server will usually be the same as for the service URL, just pointing to a different path there.

See Also:

UrlBasedRemoteAccessor.setServiceUrl(java.lang.String), CodebaseAwareObjectInputStream, RMIClassLoader

getCodebaseUrl

public String getCodebaseUrl()

Return the codebase URL to download classes from if not found locally.

Specified by:

getCodebaseUrl in interface HttpInvokerClientConfiguration

Returns:

the codebase URL, or null if none

See Also:

RMIClassLoader

setHttpInvokerRequestExecutor

public void setHttpInvokerRequestExecutor(HttpInvokerRequestExecutor httpInvokerRequestExecutor)

Set the HttpInvokerRequestExecutor implementation to use for executing remote invocations.

Default is SimpleHttpInvokerRequestExecutor. Alternatively, consider using CommonsHttpInvokerRequestExecutor for more sophisticated needs.

See Also:

SimpleHttpInvokerRequestExecutor, CommonsHttpInvokerRequestExecutor

getHttpInvokerRequestExecutor

public HttpInvokerRequestExecutor getHttpInvokerRequestExecutor()

Return the HttpInvokerRequestExecutor used by this remote accessor.

Creates a default SimpleHttpInvokerRequestExecutor if no executor has been initialized already.

setBeanClassLoader

public void setBeanClassLoader(ClassLoader classLoader)

Description copied from interface: BeanClassLoaderAware

Callback that supplies the bean class loader to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean's InitializingBean.afterPropertiesSet() method or a custom init-method.

Specified by:

setBeanClassLoader in interface BeanClassLoaderAware

Parameters:

classLoader - the owning class loader; may be null in which case a default ClassLoader must be used, for example the ClassLoader obtained via ClassUtils.getDefaultClassLoader()

getBeanClassLoader

protected final ClassLoader getBeanClassLoader()

Return the ClassLoader that this accessor operates in, to be used for deserializing and for generating proxies.

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

invoke

public Object invoke(MethodInvocation methodInvocation)
              throws Throwable

Specified by:

invoke in interface MethodInterceptor

Throws:

Throwable

executeRequest

protected RemoteInvocationResult executeRequest(RemoteInvocation invocation)
                                         throws Exception

Execute the given remote invocation via the HttpInvokerRequestExecutor.

Can be overridden in subclasses to pass a different configuration object to the executor. Alternatively, add further configuration properties in a subclass of this accessor: By default, the accessor passed itself as configuration object to the executor.

Parameters:

invocation - the RemoteInvocation to execute

Returns:

the RemoteInvocationResult object

Throws:

IOException - if thrown by I/O operations

ClassNotFoundException - if thrown during deserialization

Exception - in case of general errors

See Also:

getHttpInvokerRequestExecutor(), HttpInvokerClientConfiguration

convertHttpInvokerAccessException

protected RemoteAccessException convertHttpInvokerAccessException(Throwable ex)

Convert the given HTTP invoker access exception to an appropriate Spring RemoteAccessException.

Parameters:

ex - the exception to convert

Returns:

the RemoteAccessException to throw