javax.servlet.http
Interface HttpServletRequest


public interface HttpServletRequest
extends ServletRequest

Extends the ServletRequest interface to provide request information for HTTP servlets.

The servlet container creates an HttpServletRequest object and passes it as an argument to the servlet's service methods (doGet, doPost, etc).

Version:
$Version$
Author:
Various

Method Summary
 java.lang.String getAuthType()
          Returns the name of the authentication scheme used to protect the servlet, for example, "BASIC" or "SSL," or null if the servlet was not protected.
 java.lang.String getContextPath()
          Returns the portion of the request URI that indicates the context of the request.
 Cookie[] getCookies()
          Returns an array containing all of the Cookie objects the client sent with this request.
 long getDateHeader(java.lang.String name)
          Returns the value of the specified request header as a long value that represents a Date object.
 java.lang.String getHeader(java.lang.String name)
          Returns the value of the specified request header as a String.
 java.util.Enumeration getHeaderNames()
          Returns an enumeration of all the header names this request contains.
 java.util.Enumeration getHeaders(java.lang.String name)
          Returns all the values of the specified request header as an Enumeration of String objects.
 int getIntHeader(java.lang.String name)
          Returns the value of the specified request header as an int.
 java.lang.String getMethod()
          Returns the name of the HTTP method with which this request was made, for example, GET, POST, or PUT.
 java.lang.String getPathInfo()
          Returns any extra path information associated with the URL the client sent when it made this request.
 java.lang.String getPathTranslated()
          Returns any extra path information after the servlet name but before the query string, and translates it to a real path.
 java.lang.String getQueryString()
          Returns the query string that is contained in the request URL after the path.
 java.lang.String getRemoteUser()
          Returns the login of the user making this request, if the user has been authenticated, or null if the user has not been authenticated.
 java.lang.String getRequestedSessionId()
          Returns the session ID specified by the client.
 java.lang.String getRequestURI()
          Returns the part of this request's URL from the protocol name up to the query string in the first line of the HTTP request.
 java.lang.String getServletPath()
          Returns the part of this request's URL that calls the servlet.
 HttpSession getSession()
          Returns the current session associated with this request, or if the request does not have a session, creates one.
 HttpSession getSession(boolean create)
          Returns the current HttpSession associated with this request or, if if there is no current session and create is true, returns a new session.
 java.security.Principal getUserPrincipal()
          Returns a java.security.Principal object containing the name of the current authenticated user.
 boolean isRequestedSessionIdFromCookie()
          Checks whether the requested session ID came in as a cookie.
 boolean isRequestedSessionIdFromUrl()
          Deprecated. As of Version 2.1 of the Java Servlet API, use isRequestedSessionIdFromURL() instead.
 boolean isRequestedSessionIdFromURL()
          Checks whether the requested session ID came in as part of the request URL.
 boolean isRequestedSessionIdValid()
          Checks whether the requested session ID is still valid.
 boolean isUserInRole(java.lang.String role)
          Returns a boolean indicating whether the authenticated user is included in the specified logical "role".
 
Methods inherited from interface javax.servlet.ServletRequest
getAttribute, getAttributeNames, getCharacterEncoding, getContentLength, getContentType, getInputStream, getLocale, getLocales, getParameter, getParameterNames, getParameterValues, getProtocol, getReader, getRealPath, getRemoteAddr, getRemoteHost, getRequestDispatcher, getScheme, getServerName, getServerPort, isSecure, removeAttribute, setAttribute
 

Method Detail

getAuthType

public java.lang.String getAuthType()
Returns the name of the authentication scheme used to protect the servlet, for example, "BASIC" or "SSL," or null if the servlet was not protected.

Same as the value of the CGI variable AUTH_TYPE.

Returns:
a String specifying the name of the authentication scheme, or null if the request was not authenticated

getCookies

public Cookie[] getCookies()
Returns an array containing all of the Cookie objects the client sent with this request. This method returns null if no cookies were sent.
Returns:
an array of all the Cookies included with this request, or null if the request has no cookies

getDateHeader

public long getDateHeader(java.lang.String name)
Returns the value of the specified request header as a long value that represents a Date object. Use this method with headers that contain dates, such as If-Modified-Since.

The date is returned as the number of milliseconds since January 1, 1970 GMT. The header name is case insensitive.

If the request did not have a header of the specified name, this method returns -1. If the header can't be converted to a date, the method throws an IllegalArgumentException.

Parameters:
name - a String specifying the name of the header
Returns:
a long value representing the date specified in the header expressed as the number of milliseconds since January 1, 1970 GMT, or -1 if the named header was not included with the reqest
Throws:
java.lang.IllegalArgumentException - If the header value can't be converted to a date

getHeader

public java.lang.String getHeader(java.lang.String name)
Returns the value of the specified request header as a String. If the request did not include a header of the specified name, this method returns null. The header name is case insensitive. You can use this method with any request header.
Parameters:
name - a String specifying the header name
Returns:
a String containing the value of the requested header, or null if the request does not have a header of that name

getHeaders

public java.util.Enumeration getHeaders(java.lang.String name)
Returns all the values of the specified request header as an Enumeration of String objects.

Some headers, such as Accept-Language can be sent by clients as several headers each with a different value rather than sending the header as a comma separated list.

If the request did not include any headers of the specified name, this method returns an empty Enumeration. The header name is case insensitive. You can use this method with any request header.

Parameters:
name - a String specifying the header name
Returns:
a Enumeration containing the values of the requested header, or null if the request does not have any headers of that name

getHeaderNames

public java.util.Enumeration getHeaderNames()
Returns an enumeration of all the header names this request contains. If the request has no headers, this method returns an empty enumeration.

Some servlet containers do not allow do not allow servlets to access headers using this method, in which case this method returns null

Returns:
an enumeration of all the header names sent with this request; if the request has no headers, an empty enumeration; if the servlet container does not allow servlets to use this method, null

getIntHeader

public int getIntHeader(java.lang.String name)
Returns the value of the specified request header as an int. If the request does not have a header of the specified name, this method returns -1. If the header cannot be converted to an integer, this method throws a NumberFormatException.

The header name is case insensitive.

Parameters:
name - a String specifying the name of a request header
Returns:
an integer expressing the value of the request header or -1 if the request doesn't have a header of this name
Throws:
java.lang.NumberFormatException - If the header value can't be converted to an int

getMethod

public java.lang.String getMethod()
Returns the name of the HTTP method with which this request was made, for example, GET, POST, or PUT. Same as the value of the CGI variable REQUEST_METHOD.
Returns:
a String specifying the name of the method with which this request was made

getPathInfo

public java.lang.String getPathInfo()
Returns any extra path information associated with the URL the client sent when it made this request. The extra path information follows the servlet path but precedes the query string. This method returns null if there was no extra path information.

Same as the value of the CGI variable PATH_INFO.

Returns:
a String specifying extra path information that comes after the servlet path but before the query string in the request URL; or null if the URL does not have any extra path information

getPathTranslated

public java.lang.String getPathTranslated()
Returns any extra path information after the servlet name but before the query string, and translates it to a real path. Same as the value of the CGI variable PATH_TRANSLATED.

If the URL does not have any extra path information, this method returns null.

Returns:
a String specifying the real path, or null if the URL does not have any extra path information

getContextPath

public java.lang.String getContextPath()
Returns the portion of the request URI that indicates the context of the request. The context path always comes first in a request URI. The path starts with a "/" character but does not end with a "/" character. For servlets in the default (root) context, this method returns "".
Returns:
a String specifying the portion of the request URI that indicates the context of the request

getQueryString

public java.lang.String getQueryString()
Returns the query string that is contained in the request URL after the path. This method returns null if the URL does not have a query string. Same as the value of the CGI variable QUERY_STRING.
Returns:
a String containing the query string or null if the URL contains no query string

getRemoteUser

public java.lang.String getRemoteUser()
Returns the login of the user making this request, if the user has been authenticated, or null if the user has not been authenticated. Whether the user name is sent with each subsequent request depends on the browser and type of authentication. Same as the value of the CGI variable REMOTE_USER.
Returns:
a String specifying the login of the user making this request, or null

isUserInRole

public boolean isUserInRole(java.lang.String role)
Returns a boolean indicating whether the authenticated user is included in the specified logical "role". Roles and role membership can be defined using deployment descriptors. If the user has not been authenticated, the method returns false.
Parameters:
role - a String specifying the name of the role
Returns:
a boolean indicating whether the user making this request belongs to a given role; false if the user has not been authenticated

getUserPrincipal

public java.security.Principal getUserPrincipal()
Returns a java.security.Principal object containing the name of the current authenticated user. If the user has not been authenticated, the method returns null.
Returns:
a java.security.Principal containing the name of the user making this request; null if the user has not been authenticated

getRequestedSessionId

public java.lang.String getRequestedSessionId()
Returns the session ID specified by the client. This may not be the same as the ID of the actual session in use. For example, if the request specified an old (expired) session ID and the server has started a new session, this method gets a new session with a new ID. If the request did not specify a session ID, this method returns null.
Returns:
a String specifying the session ID, or null if the request did not specify a session ID
See Also:
isRequestedSessionIdValid()

getRequestURI

public java.lang.String getRequestURI()
Returns the part of this request's URL from the protocol name up to the query string in the first line of the HTTP request. For example:
First line of HTTP request Returned Value
POST /some/path.html HTTP/1.1/some/path.html
GET http://foo.bar/a.html HTTP/1.0 http://foo.bar/a.html
HEAD /xyz?a=b HTTP/1.1/xyz

To reconstruct an URL with a scheme and host, use HttpUtils.getRequestURL(javax.servlet.http.HttpServletRequest).

Returns:
a String containing the part of the URL from the protocol name up to the query string
See Also:
HttpUtils.getRequestURL(javax.servlet.http.HttpServletRequest)

getServletPath

public java.lang.String getServletPath()
Returns the part of this request's URL that calls the servlet. This includes either the servlet name or a path to the servlet, but does not include any extra path information or a query string. Same as the value of the CGI variable SCRIPT_NAME.
Returns:
a String containing the name or path of the servlet being called, as specified in the request URL

getSession

public HttpSession getSession(boolean create)
Returns the current HttpSession associated with this request or, if if there is no current session and create is true, returns a new session.

If create is false and the request has no valid HttpSession, this method returns null.

To make sure the session is properly maintained, you must call this method before the response is committed.

Parameters:
true - to create a new session for this request if necessary; false to return null if there's no current session
Returns:
the HttpSession associated with this request or null if create is false and the request has no valid session
See Also:
getSession()

getSession

public HttpSession getSession()
Returns the current session associated with this request, or if the request does not have a session, creates one.
Returns:
the HttpSession associated with this request
See Also:
getSession(boolean)

isRequestedSessionIdValid

public boolean isRequestedSessionIdValid()
Checks whether the requested session ID is still valid.
Returns:
true if this request has an id for a valid session in the current session context; false otherwise
See Also:
getRequestedSessionId(), getSession(boolean), HttpSessionContext

isRequestedSessionIdFromCookie

public boolean isRequestedSessionIdFromCookie()
Checks whether the requested session ID came in as a cookie.
Returns:
true if the session ID came in as a cookie; otherwise, false
See Also:
getSession(boolean)

isRequestedSessionIdFromURL

public boolean isRequestedSessionIdFromURL()
Checks whether the requested session ID came in as part of the request URL.
Returns:
true if the session ID came in as part of a URL; otherwise, false
See Also:
getSession(boolean)

isRequestedSessionIdFromUrl

public boolean isRequestedSessionIdFromUrl()
Deprecated. As of Version 2.1 of the Java Servlet API, use isRequestedSessionIdFromURL() instead.