org.apache.commons.httpclient.methods
Class ExpectContinueMethod

java.lang.Object
  org.apache.commons.httpclient.HttpMethodBase
      org.apache.commons.httpclient.methods.ExpectContinueMethod

All Implemented Interfaces:

HttpMethod

Direct Known Subclasses:

EntityEnclosingMethod, MultipartPostMethod

public abstract class ExpectContinueMethod
extends HttpMethodBase

This abstract class serves as a foundation for all HTTP methods that support 'Expect: 100-continue' handshake.

The purpose of the 100 (Continue) status (refer to section 10.1.1 of the RFC 2616 for more details) is to allow a client that is sending a request message with a request body to determine if the origin server is willing to accept the request (based on the request headers) before the client sends the request body. In some cases, it might either be inappropriate or highly inefficient for the client to send the body if the server will reject the message without looking at the body.

'Expect: 100-continue' handshake should be used with caution, as it may cause problems with HTTP servers and proxies that do not support HTTP/1.1 protocol.

Since:

2.0beta1

Author:

Oleg Kalnichevski

Field Summary

Fields inherited from class org.apache.commons.httpclient.HttpMethodBase

effectiveVersion, statusLine

Constructor Summary

ExpectContinueMethod()
No-arg constructor.

ExpectContinueMethod(String uri)
Constructor specifying a URI.

Method Summary

protected void	addRequestHeaders(HttpState state, HttpConnection conn) Sets the Expect header if it has not already been set, in addition to the "standard" set of headers.
boolean	getUseExpectHeader() Deprecated. Use HttpMethodParams
protected abstract boolean	hasRequestContent() Returns true if there is a request body to be sent.
void	setUseExpectHeader(boolean value) Deprecated. Use HttpMethodParams

Methods inherited from class org.apache.commons.httpclient.HttpMethodBase

abort, addCookieRequestHeader, addHostRequestHeader, addProxyConnectionHeader, addRequestHeader, addRequestHeader, addResponseFooter, addUserAgentRequestHeader, checkNotUsed, checkUsed, execute, generateRequestLine, getAuthenticationRealm, getContentCharSet, getDoAuthentication, getEffectiveVersion, getFollowRedirects, getHostAuthState, getHostConfiguration, getMethodRetryHandler, getName, getParams, getPath, getProxyAuthenticationRealm, getProxyAuthState, getQueryString, getRecoverableExceptionCount, getRequestCharSet, getRequestHeader, getRequestHeaderGroup, getRequestHeaders, getRequestHeaders, getResponseBody, getResponseBody, getResponseBodyAsStream, getResponseBodyAsString, getResponseBodyAsString, getResponseCharSet, getResponseContentLength, getResponseFooter, getResponseFooters, getResponseHeader, getResponseHeaderGroup, getResponseHeaders, getResponseHeaders, getResponseStream, getResponseTrailerHeaderGroup, getStatusCode, getStatusLine, getStatusText, getURI, hasBeenUsed, isAborted, isConnectionCloseForced, isHttp11, isRequestSent, isStrictMode, processCookieHeaders, processResponseBody, processResponseHeaders, processStatusLine, readResponse, readResponseBody, readResponseHeaders, readStatusLine, recycle, releaseConnection, removeRequestHeader, removeRequestHeader, responseBodyConsumed, setConnectionCloseForced, setDoAuthentication, setFollowRedirects, setHostConfiguration, setHttp11, setMethodRetryHandler, setParams, setPath, setQueryString, setQueryString, setRequestHeader, setRequestHeader, setResponseStream, setStrictMode, setURI, shouldCloseConnection, validate, writeRequest, writeRequestBody, writeRequestHeaders, writeRequestLine

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpectContinueMethod

public ExpectContinueMethod()

No-arg constructor.

Since:

2.0

ExpectContinueMethod

public ExpectContinueMethod(String uri)

Constructor specifying a URI.

Parameters:

uri - either an absolute or relative URI

Since:

2.0

Method Detail

getUseExpectHeader

public boolean getUseExpectHeader()

Deprecated. Use HttpMethodParams

Returns true if the 'Expect: 100-Continue' handshake is activated. The purpose of the 'Expect: 100-Continue' handshake to allow a client that is sending a request message with a request body to determine if the origin server is willing to accept the request (based on the request headers) before the client sends the request body.

Returns:

true if 'Expect: 100-Continue' handshake is to be used, false otherwise.

Since:

2.0beta1

See Also:

HttpMethodBase.getParams(), HttpMethodParams, HttpMethodParams.USE_EXPECT_CONTINUE

setUseExpectHeader

public void setUseExpectHeader(boolean value)

Deprecated. Use HttpMethodParams

Activates 'Expect: 100-Continue' handshake. The purpose of the 'Expect: 100-Continue' handshake to allow a client that is sending a request message with a request body to determine if the origin server is willing to accept the request (based on the request headers) before the client sends the request body.

The use of the 'Expect: 100-continue' handshake can result in noticable peformance improvement for entity enclosing requests (such as POST and PUT) that require the target server's authentication.

'Expect: 100-continue' handshake should be used with caution, as it may cause problems with HTTP servers and proxies that do not support HTTP/1.1 protocol.

Parameters:

value - boolean value

Since:

2.0beta1

See Also:

HttpMethodBase.getParams(), HttpMethodParams, HttpMethodParams.USE_EXPECT_CONTINUE

hasRequestContent

protected abstract boolean hasRequestContent()

Returns true if there is a request body to be sent. 'Expect: 100-continue' handshake may not be used if request body is not present

Returns:

boolean

Since:

2.0beta1

addRequestHeaders

protected void addRequestHeaders(HttpState state,
                                 HttpConnection conn)
                          throws IOException,
                                 HttpException

Sets the Expect header if it has not already been set, in addition to the "standard" set of headers.

Overrides:

addRequestHeaders in class HttpMethodBase

Parameters:

state - the state information associated with this method

conn - the connection used to execute this HTTP method

Throws:

IOException - if an I/O (transport) error occurs. Some transport exceptions can be recovered from.

HttpException - if a protocol exception occurs. Usually protocol exceptions cannot be recovered from.

See Also:

HttpMethodBase.writeRequestHeaders(org.apache.commons.httpclient.HttpState, org.apache.commons.httpclient.HttpConnection)