org.springframework.remoting.httpinvoker
Class CommonsHttpInvokerRequestExecutor

java.lang.Object
  org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor
      org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor

All Implemented Interfaces:

HttpInvokerRequestExecutor

public class CommonsHttpInvokerRequestExecutor
extends AbstractHttpInvokerRequestExecutor

HttpInvokerRequestExecutor implementation that uses Jakarta Commons HttpClient to execute POST requests. Compatible with Commons HttpClient 2.0 and 3.0.

Allows to use a preconfigured HttpClient instance, potentially with authentication, HTTP connection pooling, etc. Also designed for easy subclassing, customizing specific template methods.

Since:

1.1

Author:

Juergen Hoeller

See Also:

SimpleHttpInvokerRequestExecutor

Field Summary

Fields inherited from class org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor

CONTENT_TYPE_SERIALIZED_OBJECT, ENCODING_GZIP, HTTP_HEADER_ACCEPT_ENCODING, HTTP_HEADER_CONTENT_ENCODING, HTTP_HEADER_CONTENT_LENGTH, HTTP_HEADER_CONTENT_TYPE, HTTP_METHOD_POST, logger

Constructor Summary

CommonsHttpInvokerRequestExecutor()
Create a new CommonsHttpInvokerRequestExecutor with a default HttpClient that uses a default MultiThreadedHttpConnectionManager.

CommonsHttpInvokerRequestExecutor(HttpClient httpClient)
Create a new CommonsHttpInvokerRequestExecutor with the given HttpClient instance.

Method Summary

protected PostMethod	createPostMethod(HttpInvokerClientConfiguration config) Create a PostMethod for the given configuration.
protected RemoteInvocationResult	doExecuteRequest(HttpInvokerClientConfiguration config, ByteArrayOutputStream baos) Execute the given request through Commons HttpClient.
protected void	executePostMethod(HttpInvokerClientConfiguration config, HttpClient httpClient, PostMethod postMethod) Execute the given PostMethod instance.
HttpClient	getHttpClient() Return the HttpClient instance that this request executor uses.
protected InputStream	getResponseBody(HttpInvokerClientConfiguration config, PostMethod postMethod) Extract the response body from the given executed remote invocation request.
protected boolean	isGzipResponse(PostMethod postMethod) Determine whether the given response is a GZIP response.
void	setHttpClient(HttpClient httpClient) Set the HttpClient instance to use for this request executor.
protected void	setRequestBody(HttpInvokerClientConfiguration config, PostMethod postMethod, ByteArrayOutputStream baos) Set the given serialized remote invocation as request body.
protected void	validateResponse(HttpInvokerClientConfiguration config, PostMethod postMethod) Validate the given response as contained in the PostMethod object, throwing an exception if it does not correspond to a successful HTTP response.

Methods inherited from class org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor

createObjectInputStream, decorateInputStream, decorateOutputStream, doReadRemoteInvocationResult, doWriteRemoteInvocation, executeRequest, getByteArrayOutputStream, getContentType, isAcceptGzipEncoding, readRemoteInvocationResult, setAcceptGzipEncoding, setContentType, writeRemoteInvocation

Methods inherited from class java.lang.Object

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

Constructor Detail

CommonsHttpInvokerRequestExecutor

public CommonsHttpInvokerRequestExecutor()

Create a new CommonsHttpInvokerRequestExecutor with a default HttpClient that uses a default MultiThreadedHttpConnectionManager.

See Also:

HttpClient, MultiThreadedHttpConnectionManager

CommonsHttpInvokerRequestExecutor

public CommonsHttpInvokerRequestExecutor(HttpClient httpClient)

Create a new CommonsHttpInvokerRequestExecutor with the given HttpClient instance.

Parameters:

httpClient - the HttpClient instance to use for this request executor

Method Detail

setHttpClient

public void setHttpClient(HttpClient httpClient)

Set the HttpClient instance to use for this request executor.

getHttpClient

public HttpClient getHttpClient()

Return the HttpClient instance that this request executor uses.

doExecuteRequest

protected RemoteInvocationResult doExecuteRequest(HttpInvokerClientConfiguration config,
                                                  ByteArrayOutputStream baos)
                                           throws IOException,
                                                  ClassNotFoundException

Execute the given request through Commons HttpClient.

This method implements the basic processing workflow: The actual work happens in this class's template methods.

Specified by:

doExecuteRequest in class AbstractHttpInvokerRequestExecutor

Parameters:

config - the HTTP invoker configuration that specifies the target service

baos - the ByteArrayOutputStream that contains the serialized RemoteInvocation object

Returns:

the RemoteInvocationResult object

Throws:

IOException - if thrown by I/O operations

ClassNotFoundException - if thrown during deserialization

See Also:

createPostMethod(org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration), setRequestBody(org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration, org.apache.commons.httpclient.methods.PostMethod, java.io.ByteArrayOutputStream), executePostMethod(org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration, org.apache.commons.httpclient.HttpClient, org.apache.commons.httpclient.methods.PostMethod), validateResponse(org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration, org.apache.commons.httpclient.methods.PostMethod), getResponseBody(org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration, org.apache.commons.httpclient.methods.PostMethod)

createPostMethod

protected PostMethod createPostMethod(HttpInvokerClientConfiguration config)
                               throws IOException

Create a PostMethod for the given configuration.

The default implementation creates a standard PostMethod with "application/x-java-serialized-object" as "Content-Type" header.

Parameters:

config - the HTTP invoker configuration that specifies the target service

Returns:

the PostMethod instance

Throws:

IOException - if thrown by I/O methods

setRequestBody

protected void setRequestBody(HttpInvokerClientConfiguration config,
                              PostMethod postMethod,
                              ByteArrayOutputStream baos)
                       throws IOException

Set the given serialized remote invocation as request body.

The default implementation simply sets the serialized invocation as the PostMethod's request body. This can be overridden, for example, to write a specific encoding and potentially set appropriate HTTP request headers.

Parameters:

config - the HTTP invoker configuration that specifies the target service

postMethod - the PostMethod to set the request body on

baos - the ByteArrayOutputStream that contains the serialized RemoteInvocation object

Throws:

IOException - if thrown by I/O methods

See Also:

EntityEnclosingMethod.setRequestBody(java.io.InputStream), EntityEnclosingMethod.setRequestEntity(org.apache.commons.httpclient.methods.RequestEntity), InputStreamRequestEntity

executePostMethod

protected void executePostMethod(HttpInvokerClientConfiguration config,
                                 HttpClient httpClient,
                                 PostMethod postMethod)
                          throws IOException

Execute the given PostMethod instance.

Parameters:

config - the HTTP invoker configuration that specifies the target service

httpClient - the HttpClient to execute on

postMethod - the PostMethod to execute

Throws:

IOException - if thrown by I/O methods

See Also:

HttpClient.executeMethod(org.apache.commons.httpclient.HttpMethod)

validateResponse

protected void validateResponse(HttpInvokerClientConfiguration config,
                                PostMethod postMethod)
                         throws IOException

Validate the given response as contained in the PostMethod object, throwing an exception if it does not correspond to a successful HTTP response.

Default implementation rejects any HTTP status code beyond 2xx, to avoid parsing the response body and trying to deserialize from a corrupted stream.

Parameters:

config - the HTTP invoker configuration that specifies the target service

postMethod - the executed PostMethod to validate

Throws:

IOException - if validation failed

See Also:

HttpMethodBase.getStatusCode(), HttpException

getResponseBody

protected InputStream getResponseBody(HttpInvokerClientConfiguration config,
                                      PostMethod postMethod)
                               throws IOException

Extract the response body from the given executed remote invocation request.

The default implementation simply fetches the PostMethod's response body stream. If the response is recognized as GZIP response, the InputStream will get wrapped in a GZIPInputStream.

Parameters:

config - the HTTP invoker configuration that specifies the target service

postMethod - the PostMethod to read the response body from

Returns:

an InputStream for the response body

Throws:

IOException - if thrown by I/O methods

See Also:

isGzipResponse(org.apache.commons.httpclient.methods.PostMethod), GZIPInputStream, HttpMethodBase.getResponseBodyAsStream(), HttpMethodBase.getResponseHeader(String)

isGzipResponse

protected boolean isGzipResponse(PostMethod postMethod)

Determine whether the given response is a GZIP response.

Default implementation checks whether the HTTP "Content-Encoding" header contains "gzip" (in any casing).

Parameters:

postMethod - the PostMethod to check