public interface HttpServletRequest extends ServletRequest
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).
| Modifier and Type | Field and Description | 
|---|---|
| static java.lang.String | BASIC_AUTHString identifier for Basic authentication. | 
| static java.lang.String | CLIENT_CERT_AUTHString identifier for Client Certificate authentication. | 
| static java.lang.String | DIGEST_AUTHString identifier for Digest authentication. | 
| static java.lang.String | FORM_AUTHString identifier for Form authentication. | 
| Modifier and Type | Method and Description | 
|---|---|
| boolean | authenticate(HttpServletResponse response)Triggers the same authentication process as would be triggered if the
 request is for a resource that is protected by a security constraint. | 
| java.lang.String | getAuthType()Returns the name of the authentication scheme used to protect the
 servlet. | 
| 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  Cookieobjects the
 client sent with this request. | 
| long | getDateHeader(java.lang.String name)Returns the value of the specified request header as a  longvalue that represents aDateobject. | 
| java.lang.String | getHeader(java.lang.String name)Returns the value of the specified request header as a
  String. | 
| java.util.Enumeration<java.lang.String> | getHeaderNames()Returns an enumeration of all the header names this request contains. | 
| java.util.Enumeration<java.lang.String> | getHeaders(java.lang.String name)Returns all the values of the specified request header as an
  EnumerationofStringobjects. | 
| 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. | 
| Part | getPart(java.lang.String name)Gets the named Part or null if the Part does not exist. | 
| java.util.Collection<Part> | getParts()Return a collection of all uploaded Parts. | 
| 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  nullif 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.StringBuffer | getRequestURL()Reconstructs the URL the client used to make the 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  HttpSessionassociated with this request
 or, if there is no current session andcreateis true,
 returns a new session. | 
| java.security.Principal | getUserPrincipal()Returns a  java.security.Principalobject 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". | 
| void | login(java.lang.String username,
     java.lang.String password)Authenticate the provided user name and password and then associated the
 authenticated user with the request. | 
| void | logout()Removes any authenticated user from the request. | 
getAsyncContext, getAttribute, getAttributeNames, getCharacterEncoding, getContentLength, getContentType, getDispatcherType, getInputStream, getLocalAddr, getLocale, getLocales, getLocalName, getLocalPort, getParameter, getParameterMap, getParameterNames, getParameterValues, getProtocol, getReader, getRealPath, getRemoteAddr, getRemoteHost, getRemotePort, getRequestDispatcher, getScheme, getServerName, getServerPort, getServletContext, isAsyncStarted, isAsyncSupported, isSecure, removeAttribute, setAttribute, setCharacterEncoding, startAsync, startAsyncstatic final java.lang.String BASIC_AUTH
static final java.lang.String FORM_AUTH
static final java.lang.String CLIENT_CERT_AUTH
static final java.lang.String DIGEST_AUTH
java.lang.String getAuthType()
null is
 returned.
 Same as the value of the CGI variable AUTH_TYPE.
null if the request was not authenticated.Cookie[] getCookies()
Cookie objects the
 client sent with this request. This method returns null if
 no cookies were sent.Cookies included with this
         request, or null if the request has no cookieslong getDateHeader(java.lang.String name)
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.
name - a String specifying the name of the headerlong 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
         requestjava.lang.IllegalArgumentException - If the header value can't be converted to a datejava.lang.String getHeader(java.lang.String name)
String. If the request did not include a header of the
 specified name, this method returns null. If there are
 multiple headers with the same name, this method returns the first head
 in the request. The header name is case insensitive. You can use this
 method with any request header.name - a String specifying the header nameString containing the value of the requested
         header, or null if the request does not have a
         header of that namejava.util.Enumeration<java.lang.String> getHeaders(java.lang.String name)
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.
name - a String specifying the header nameEnumeration containing the values of the requested
         header. If the request does not have any headers of that name
         return an empty enumeration. If the container does not allow
         access to header information, return nulljava.util.Enumeration<java.lang.String> getHeaderNames()
 Some servlet containers do not allow servlets to access headers using
 this method, in which case this method returns null
nullint getIntHeader(java.lang.String name)
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.
name - a String specifying the name of a request headerjava.lang.NumberFormatException - If the header value can't be converted to an
                intjava.lang.String getMethod()
String specifying the name of the method with
         which this request was madejava.lang.String getPathInfo()
 This method returns null if there was no extra path
 information.
 
Same as the value of the CGI variable PATH_INFO.
String, decoded by the web container, 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 informationjava.lang.String getPathTranslated()
 If the URL does not have any extra path information, this method returns
 null or the servlet container cannot translate the virtual
 path to a real path for any reason (such as when the web application is
 executed from an archive). The web container does not decode this string.
String specifying the real path, or
         null if the URL does not have any extra path
         informationjava.lang.String getContextPath()
String specifying the portion of the request URI
         that indicates the context of the requestjava.lang.String getQueryString()
null if the URL does not have a
 query string. Same as the value of the CGI variable QUERY_STRING.String containing the query string or
         null if the URL contains no query string. The value
         is not decoded by the container.java.lang.String getRemoteUser()
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.String specifying the login of the user making
         this request, or null if the user login is not knownboolean isUserInRole(java.lang.String role)
false.role - a String specifying the name of the roleboolean indicating whether the user making this
         request belongs to a given role; false if the user
         has not been authenticatedjava.security.Principal getUserPrincipal()
java.security.Principal object containing the name
 of the current authenticated user. If the user has not been
 authenticated, the method returns null.java.security.Principal containing the name of the
         user making this request; null if the user has not
         been authenticatedjava.lang.String getRequestedSessionId()
null.String specifying the session ID, or
         null if the request did not specify a session IDisRequestedSessionIdValid()java.lang.String getRequestURI()
| 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 | /a.html | |
| HEAD /xyz?a=b HTTP/1.1 | /xyz | 
 To reconstruct a URL with a scheme and host, use
 getRequestURL().
String containing the part of the URL from the
         protocol name up to the query stringgetRequestURL()java.lang.StringBuffer getRequestURL()
 Because this method returns a StringBuffer, not a string,
 you can modify the URL easily, for example, to append query parameters.
 
This method is useful for creating redirect messages and for reporting errors.
StringBuffer object containing the reconstructed
         URLjava.lang.String getServletPath()
This method will return an empty string ("") if the servlet used to process this request was matched using the "/*" pattern.
String containing the name or path of the servlet
         being called, as specified in the request URL, decoded, or an
         empty string if the servlet used to process the request is
         matched using the "/*" pattern.HttpSession getSession(boolean create)
HttpSession associated with this request
 or, 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. If the container is using cookies to maintain session integrity and is asked to create a new session when the response is committed, an IllegalStateException is thrown.
create - true to create a new session for this request if
            necessary; false to return null if
            there's no current sessionHttpSession associated with this request or
         null if create is false
         and the request has no valid sessiongetSession()HttpSession getSession()
HttpSession associated with this requestgetSession(boolean)boolean isRequestedSessionIdValid()
true if this request has an id for a valid session
         in the current session context; false otherwisegetRequestedSessionId(), 
getSession(boolean)boolean isRequestedSessionIdFromCookie()
true if the session ID came in as a cookie;
         otherwise, falsegetSession(boolean)boolean isRequestedSessionIdFromURL()
true if the session ID came in as part of a URL;
         otherwise, falsegetSession(boolean)boolean isRequestedSessionIdFromUrl()
isRequestedSessionIdFromURL() instead.isRequestedSessionIdFromURL()boolean authenticate(HttpServletResponse response) throws java.io.IOException, ServletException
response - The response to use to return any authentication
                  challengetrue if the user is successfully authenticated and
         false if notjava.io.IOException - if the authentication process attempted to read from
         the request or write to the response and an I/O error occurredjava.lang.IllegalStateException - if the authentication process attempted to
         write to the response after it had been committedServletException - if the authentication failed and the caller is
         expected to handle the failurevoid login(java.lang.String username,
         java.lang.String password)
           throws ServletException
username - The user name to authenticatepassword - The password to use to authenticate the userServletException - If any of getRemoteUser(),
             getUserPrincipal() or getAuthType() are
             non-null, if the configured authenticator does not support
             user name and password authentication or if the
             authentication failsvoid logout()
            throws ServletException
ServletException - If the logout failsjava.util.Collection<Part> getParts() throws java.io.IOException, java.lang.IllegalStateException, ServletException
java.io.IOException - if an I/O error occursjava.lang.IllegalStateException - if size limits are exceeded or no multipart configuration is
             providedServletException - if the request is not multipart/form-dataPart getPart(java.lang.String name) throws java.io.IOException, java.lang.IllegalStateException, ServletException
name - The name of the Part to obtainjava.io.IOException - if an I/O error occursjava.lang.IllegalStateException - if size limits are exceededServletException - if the request is not multipart/form-dataCopyright © 2000-2020 Apache Software Foundation. All Rights Reserved.