## org.springframework.remoting.httpinvoker
Class HttpInvokerClientInterceptor

    java.lang.Object
      org.springframework.remoting.support.RemotingSupport
          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

`MethodInterceptor` 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.RemotingSupport
`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 RemoteInvocationResult` `executeRequest(RemoteInvocation invocation, MethodInvocation originalInvocation)` Execute the given remote invocation via the HttpInvokerRequestExecutor.
`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` `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 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`

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.

### 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,
                                                    MethodInvocation originalInvocation)
                                             throws Exception

  Execute the given remote invocation via the HttpInvokerRequestExecutor.

  This implementation delegates to `executeRequest(RemoteInvocation)`. Can be overridden to react to the specific original MethodInvocation.

  Parameters:
    `invocation` - the RemoteInvocation to execute
    `originalInvocation` - the original MethodInvocation (can e.g. be cast to the ProxyMethodInvocation interface for accessing user attributes)
  Returns:
    the RemoteInvocationResult object
  Throws:
    `Exception` - in case of errors

### 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