org.apache.http.protocol
Class HttpRequestExecutor

java.lang.Object
  org.apache.http.protocol.HttpRequestExecutor

@Contract(threading=IMMUTABLE)
public class HttpRequestExecutor
extends Object

HttpRequestExecutor is a client side HTTP protocol handler based on the blocking (classic) I/O model.

HttpRequestExecutor relies on HttpProcessor to generate mandatory protocol headers for all outgoing messages and apply common, cross-cutting message transformations to all incoming and outgoing messages. Application specific processing can be implemented outside HttpRequestExecutor once the request has been executed and a response has been received.

Since:

4.0

Field Summary

static int

DEFAULT_WAIT_FOR_CONTINUE

Constructor Summary

HttpRequestExecutor()

HttpRequestExecutor(int waitForContinue)
Creates new instance of HttpRequestExecutor.

Method Summary

protected boolean	canResponseHaveBody(HttpRequest request, HttpResponse response) Decide whether a response comes with an entity.
protected HttpResponse	doReceiveResponse(HttpRequest request, HttpClientConnection conn, HttpContext context) Waits for and receives a response.
protected HttpResponse	doSendRequest(HttpRequest request, HttpClientConnection conn, HttpContext context) Send the given request over the given connection.
HttpResponse	execute(HttpRequest request, HttpClientConnection conn, HttpContext context) Sends the request and obtain a response.
void	postProcess(HttpResponse response, HttpProcessor processor, HttpContext context) Post-processes the given response using the given protocol processor and completes the process of request execution.
void	preProcess(HttpRequest request, HttpProcessor processor, HttpContext context) Pre-process the given request using the given protocol processor and initiates the process of request execution.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_WAIT_FOR_CONTINUE

public static final int DEFAULT_WAIT_FOR_CONTINUE

See Also:

Constant Field Values

Constructor Detail

HttpRequestExecutor

public HttpRequestExecutor(int waitForContinue)

Creates new instance of HttpRequestExecutor.

Since:

4.3

HttpRequestExecutor

public HttpRequestExecutor()

Method Detail

canResponseHaveBody

protected boolean canResponseHaveBody(HttpRequest request,
                                      HttpResponse response)

Decide whether a response comes with an entity. The implementation in this class is based on RFC 2616.

Derived executors can override this method to handle methods and response codes not specified in RFC 2616.

Parameters:

request - the request, to obtain the executed method

response - the response, to obtain the status code

execute

public HttpResponse execute(HttpRequest request,
                            HttpClientConnection conn,
                            HttpContext context)
                     throws IOException,
                            HttpException

Sends the request and obtain a response.

Parameters:

request - the request to execute.

conn - the connection over which to execute the request.

Returns:

the response to the request.

Throws:

IOException - in case of an I/O error.

HttpException - in case of HTTP protocol violation or a processing problem.

preProcess

public void preProcess(HttpRequest request,
                       HttpProcessor processor,
                       HttpContext context)
                throws HttpException,
                       IOException

Pre-process the given request using the given protocol processor and initiates the process of request execution.

Parameters:

request - the request to prepare

processor - the processor to use

context - the context for sending the request

Throws:

IOException - in case of an I/O error.

HttpException - in case of HTTP protocol violation or a processing problem.

doSendRequest

protected HttpResponse doSendRequest(HttpRequest request,
                                     HttpClientConnection conn,
                                     HttpContext context)
                              throws IOException,
                                     HttpException

Send the given request over the given connection.

This method also handles the expect-continue handshake if necessary. If it does not have to handle an expect-continue handshake, it will not use the connection for reading or anything else that depends on data coming in over the connection.

Parameters:

request - the request to send, already preprocessed

conn - the connection over which to send the request, already established

context - the context for sending the request

Returns:

a terminal response received as part of an expect-continue handshake, or null if the expect-continue handshake is not used

Throws:

IOException - in case of an I/O error.

HttpException - in case of HTTP protocol violation or a processing problem.

doReceiveResponse

protected HttpResponse doReceiveResponse(HttpRequest request,
                                         HttpClientConnection conn,
                                         HttpContext context)
                                  throws HttpException,
                                         IOException

Waits for and receives a response. This method will automatically ignore intermediate responses with status code 1xx.

Parameters:

request - the request for which to obtain the response

conn - the connection over which the request was sent

context - the context for receiving the response

Returns:

the terminal response, not yet post-processed

Throws:

IOException - in case of an I/O error.

HttpException - in case of HTTP protocol violation or a processing problem.

postProcess

public void postProcess(HttpResponse response,
                        HttpProcessor processor,
                        HttpContext context)
                 throws HttpException,
                        IOException

Post-processes the given response using the given protocol processor and completes the process of request execution.

This method does not read the response entity, if any. The connection over which content of the response entity is being streamed from cannot be reused until EntityUtils.consume(org.apache.http.HttpEntity) has been invoked.

Parameters:

response - the response object to post-process

processor - the processor to use

context - the context for post-processing the response

Throws:

IOException - in case of an I/O error.

HttpException - in case of HTTP protocol violation or a processing problem.