org.apache.commons.httpclient.methods: abstract public class: ExpectContinueMethod

org.apache.commons.httpclient.methods
abstract public class: ExpectContinueMethod [javadoc | source]

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

All Implemented Interfaces:
HttpMethod

Direct Known Subclasses:
PutMethod, NoncompliantPostMethod, PostMethod, EntityEnclosingMethod, UrlPostMethod, MultipartPostMethod, UrlPutMethod

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.

author: < - a href="mailto:oleg@ural.ru">Oleg Kalnichevski

since: 2.0beta1 -

Fields inherited from org.apache.commons.httpclient.HttpMethodBase:
statusLine, effectiveVersion

Constructor:

Constructor:
public ExpectContinueMethod() { super(); } No-arg constructor. since: `2.0` -
public ExpectContinueMethod(String uri) { super(uri); } Constructor specifying a URI. Parameters: `uri` - either an absolute or relative URI since: `2.0` -

 public ExpectContinueMethod() {
             
        super();
}

No-arg constructor.

since: 2.0 -

 public ExpectContinueMethod(String uri) {
        super(uri);
}

Constructor specifying a URI.

Parameters:

uri - either an absolute or relative URI

since: 2.0 -

Method from org.apache.commons.httpclient.methods.ExpectContinueMethod Summary:
addRequestHeaders, getUseExpectHeader, hasRequestContent, setUseExpectHeader

Methods from org.apache.commons.httpclient.HttpMethodBase:
abort, addCookieRequestHeader, addHostRequestHeader, addProxyConnectionHeader, addRequestHeader, addRequestHeader, addRequestHeaders, addResponseFooter, addUserAgentRequestHeader, checkNotUsed, checkUsed, execute, fakeResponse, generateRequestLine, getAuthenticationRealm, getContentCharSet, getDoAuthentication, getEffectiveVersion, getFollowRedirects, getHostAuthState, getHostConfiguration, getMethodRetryHandler, getName, getParams, getPath, getProxyAuthState, getProxyAuthenticationRealm, 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 from org.apache.commons.httpclient.HttpMethodBase:

abort, addCookieRequestHeader, addHostRequestHeader, addProxyConnectionHeader, addRequestHeader, addRequestHeader, addRequestHeaders, addResponseFooter, addUserAgentRequestHeader, checkNotUsed, checkUsed, execute, fakeResponse, generateRequestLine, getAuthenticationRealm, getContentCharSet, getDoAuthentication, getEffectiveVersion, getFollowRedirects, getHostAuthState, getHostConfiguration, getMethodRetryHandler, getName, getParams, getPath, getProxyAuthState, getProxyAuthenticationRealm, 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 from java.lang.Object:
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from org.apache.commons.httpclient.methods.ExpectContinueMethod Detail:
protected void addRequestHeaders(HttpState state, HttpConnection conn) throws IOException, HttpException { LOG.trace("enter ExpectContinueMethod.addRequestHeaders(HttpState, HttpConnection)"); super.addRequestHeaders(state, conn); // If the request is being retried, the header may already be present boolean headerPresent = (getRequestHeader("Expect") != null); // See if the expect header should be sent // = HTTP/1.1 or higher // = request body present if (getParams().isParameterTrue(HttpMethodParams.USE_EXPECT_CONTINUE) && getEffectiveVersion().greaterEquals(HttpVersion.HTTP_1_1) && hasRequestContent()) { if (!headerPresent) { setRequestHeader("Expect", "100-continue"); } } else { if (headerPresent) { removeRequestHeader("Expect"); } } } Sets the `Expect` header if it has not already been set, in addition to the "standard" set of headers.
public boolean getUseExpectHeader() { return getParams().getBooleanParameter(HttpMethodParams.USE_EXPECT_CONTINUE, false); } 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.
abstract protected 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
public void setUseExpectHeader(boolean value) { getParams().setBooleanParameter(HttpMethodParams.USE_EXPECT_CONTINUE, 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.

Method from org.apache.commons.httpclient.methods.ExpectContinueMethod Detail:

 protected  void addRequestHeaders(HttpState state,
    HttpConnection conn) throws IOException, HttpException {
        LOG.trace("enter ExpectContinueMethod.addRequestHeaders(HttpState, HttpConnection)");
        super.addRequestHeaders(state, conn);
        // If the request is being retried, the header may already be present
        boolean headerPresent = (getRequestHeader("Expect") != null);
        // See if the expect header should be sent
        // = HTTP/1.1 or higher
        // = request body present
        if (getParams().isParameterTrue(HttpMethodParams.USE_EXPECT_CONTINUE) 
        && getEffectiveVersion().greaterEquals(HttpVersion.HTTP_1_1) 
        && hasRequestContent())
        {
            if (!headerPresent) {
                setRequestHeader("Expect", "100-continue");
            }
        } else {
            if (headerPresent) {
                removeRequestHeader("Expect");
            }
        }
}

Expect

 public boolean getUseExpectHeader() {
        return getParams().getBooleanParameter(HttpMethodParams.USE_EXPECT_CONTINUE, false);
}

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.

 abstract protected 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

 public  void setUseExpectHeader(boolean value) {
        getParams().setBooleanParameter(HttpMethodParams.USE_EXPECT_CONTINUE, 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.