HttpServletRequest.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jakarta.servlet.http;
import java.io.IOException;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Map;
import jakarta.servlet.ServletException;
import jakarta.servlet.ServletRequest;
/**
* Extends the {@link jakarta.servlet.ServletRequest} interface to provide request information for HTTP servlets.
* <p>
* The servlet container creates an <code>HttpServletRequest</code> object and passes it as an argument to the servlet's
* service methods (<code>doGet</code>, <code>doPost</code>, etc).
*/
public interface HttpServletRequest extends ServletRequest {
/**
* String identifier for Basic authentication. Value "BASIC"
*/
String BASIC_AUTH = "BASIC";
/**
* String identifier for Form authentication. Value "FORM"
*/
String FORM_AUTH = "FORM";
/**
* String identifier for Client Certificate authentication. Value "CLIENT_CERT"
*/
String CLIENT_CERT_AUTH = "CLIENT_CERT";
/**
* String identifier for Digest authentication. Value "DIGEST"
*/
String DIGEST_AUTH = "DIGEST";
/**
* Returns the name of the authentication scheme used to protect the servlet. All servlet containers support basic,
* form and client certificate authentication, and may additionally support digest authentication. If the servlet is
* not authenticated <code>null</code> is returned.
* <p>
* Same as the value of the CGI variable AUTH_TYPE.
*
* @return one of the static members BASIC_AUTH, FORM_AUTH, CLIENT_CERT_AUTH, DIGEST_AUTH (suitable for ==
* comparison) or the container-specific string indicating the authentication scheme, or
* <code>null</code> if the request was not authenticated.
*/
String getAuthType();
/**
* Returns an array containing all of the <code>Cookie</code> objects the client sent with this request. This method
* returns <code>null</code> if no cookies were sent.
*
* @return an array of all the <code>Cookies</code> included with this request, or <code>null</code> if the request
* has no cookies
*/
Cookie[] getCookies();
/**
* Returns the value of the specified request header as a <code>long</code> value that represents a
* <code>Date</code> object. Use this method with headers that contain dates, such as
* <code>If-Modified-Since</code>.
* <p>
* The date is returned as the number of milliseconds since January 1, 1970 GMT. The header name is case
* insensitive.
* <p>
* 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 <code>IllegalArgumentException</code>.
*
* @param name a <code>String</code> specifying the name of the header
*
* @return a <code>long</code> 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 request
*
* @exception IllegalArgumentException If the header value can't be converted to a date
*/
long getDateHeader(String name);
/**
* Returns the value of the specified request header as a <code>String</code>. If the request did not include a
* header of the specified name, this method returns <code>null</code>. 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.
*
* @param name a <code>String</code> specifying the header name
*
* @return a <code>String</code> containing the value of the requested header, or <code>null</code> if the request
* does not have a header of that name
*/
String getHeader(String name);
/**
* Returns all the values of the specified request header as an <code>Enumeration</code> of <code>String</code>
* objects.
* <p>
* Some headers, such as <code>Accept-Language</code> can be sent by clients as several headers each with a
* different value rather than sending the header as a comma separated list.
* <p>
* If the request did not include any headers of the specified name, this method returns an empty
* <code>Enumeration</code>. The header name is case insensitive. You can use this method with any request header.
*
* @param name a <code>String</code> specifying the header name
*
* @return an <code>Enumeration</code> 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 null
*/
Enumeration<String> getHeaders(String name);
/**
* Returns an enumeration of all the header names this request contains. If the request has no headers, this method
* returns an empty enumeration.
* <p>
* Some servlet containers do not allow servlets to access headers using this method, in which case this method
* returns <code>null</code>
*
* @return 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, <code>null</code>
*/
Enumeration<String> getHeaderNames();
/**
* Returns the value of the specified request header as an <code>int</code>. 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 <code>NumberFormatException</code>.
* <p>
* The header name is case insensitive.
*
* @param name a <code>String</code> specifying the name of a request header
*
* @return an integer expressing the value of the request header or -1 if the request doesn't have a header of this
* name
*
* @exception NumberFormatException If the header value can't be converted to an <code>int</code>
*/
int getIntHeader(String name);
/**
* Obtain the mapping information for this request.
*
* @return the mapping information for this request
*/
default HttpServletMapping getHttpServletMapping() {
return new HttpServletMapping() {
@Override
public String getMatchValue() {
return "";
}
@Override
public String getPattern() {
return "";
}
@Override
public String getServletName() {
return "";
}
@Override
public MappingMatch getMappingMatch() {
return null;
}
};
}
/**
* 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.
*
* @return a <code>String</code> specifying the name of the method with which this request was made
*/
String getMethod();
/**
* 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 and will start with a "/" character.
* <p>
* This method returns <code>null</code> if there was no extra path information.
* <p>
* The URL will be canonicalized as per section 3.5 of the specification before the path information, if any, is
* extracted.
*
* @return a <code>String</code>, canonicalized by the web container, specifying extra path information that comes
* after the servlet path but before the query string in the request URL; or {@code null} if the URL
* does not have any extra path information
*/
String getPathInfo();
/**
* 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.
* <p>
* If the URL does not have any extra path information, this method returns <code>null</code> 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.
*
* @return a <code>String</code> specifying the real path, or <code>null</code> if the URL does not have any extra
* path information
*/
String getPathTranslated();
/**
* Obtain a builder for generating push requests. {@link PushBuilder} documents how this request will be used as the
* basis for a push request. Each call to this method will return a new instance, independent of any previous
* instance obtained.
*
* @return A builder that can be used to generate push requests based on this request or {@code null} if push is not
* supported. Note that even if a PushBuilder instance is returned, by the time that
* {@link PushBuilder#push()} is called, it may no longer be valid to push a request and the push
* request will be ignored.
*
* @since Servlet 4.0
*/
default PushBuilder newPushBuilder() {
return null;
}
/**
* 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 "". The container does not decode this string.
*
* @return a <code>String</code> specifying the portion of the request URI that indicates the context of the request
*/
String getContextPath();
/**
* Returns the query string that is contained in the request URL after the path. This method returns
* <code>null</code> if the URL does not have a query string. Same as the value of the CGI variable QUERY_STRING.
*
* @return a <code>String</code> containing the query string or <code>null</code> if the URL contains no query
* string. The value is not decoded by the container.
*/
String getQueryString();
/**
* Returns the login of the user making this request, if the user has been authenticated, or <code>null</code> 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.
*
* @return a <code>String</code> specifying the login of the user making this request, or <code>null</code> if the
* user login is not known
*/
String getRemoteUser();
/**
* 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 <code>false</code>.
*
* @param role a <code>String</code> specifying the name of the role
*
* @return a <code>boolean</code> indicating whether the user making this request belongs to a given role;
* <code>false</code> if the user has not been authenticated
*/
boolean isUserInRole(String role);
/**
* Returns a <code>java.security.Principal</code> object containing the name of the current authenticated user. If
* the user has not been authenticated, the method returns <code>null</code>.
*
* @return a <code>java.security.Principal</code> containing the name of the user making this request;
* <code>null</code> if the user has not been authenticated
*/
java.security.Principal getUserPrincipal();
/**
* Returns the session ID specified by the client. This may not be the same as the ID of the current valid session
* for this request. If the client did not specify a session ID, this method returns <code>null</code>.
*
* @return a <code>String</code> specifying the session ID, or <code>null</code> if the request did not specify a
* session ID
*
* @see #isRequestedSessionIdValid
*/
String getRequestedSessionId();
/**
* 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. The web container does not decode this String. For example:
* <table>
* <caption>Examples of Returned Values</caption>
* <tr>
* <th>First line of HTTP request</th>
* <th>Returned Value</th>
* <tr>
* <td>POST /some/path.html HTTP/1.1
* <td>
* <td>/some/path.html
* <tr>
* <td>GET http://foo.bar/a.html HTTP/1.0
* <td>
* <td>/a.html
* <tr>
* <td>HEAD /xyz?a=b HTTP/1.1
* <td>
* <td>/xyz
* </table>
* <p>
* To reconstruct a URL with a scheme and host, use {@link #getRequestURL}.
*
* @return a <code>String</code> containing the part of the URL from the protocol name up to the query string
*
* @see #getRequestURL
*/
String getRequestURI();
/**
* Reconstructs the URL the client used to make the request. The returned URL contains a protocol, server name, port
* number, and server path, but it does not include query string parameters.
* <p>
* Because this method returns a <code>StringBuffer</code>, not a string, you can modify the URL easily, for
* example, to append query parameters.
* <p>
* This method is useful for creating redirect messages and for reporting errors.
*
* @return a <code>StringBuffer</code> object containing the reconstructed URL
*/
StringBuffer getRequestURL();
/**
* Returns the part of this request's URL that calls the servlet. This path starts with a "/" character and 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.
* <p>
* The URL will be canonicalized as per section 3.5 of the specification before the path information, if any, is
* extracted.
* <p>
* This method will return an empty string ("") if the servlet used to process this request was matched using the
* "/*" pattern.
*
* @return a <code>String</code>, canonicalized by the web container, containing the name or path of the servlet
* being called, as specified in the request URL, or an empty string if the servlet used to process the
* request is matched using the "/*" pattern.
*/
String getServletPath();
/**
* Returns the current <code>HttpSession</code> associated with this request or, if there is no current session and
* <code>create</code> is true, returns a new session.
* <p>
* If <code>create</code> is <code>false</code> and the request has no valid <code>HttpSession</code>, this method
* returns <code>null</code>.
* <p>
* 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.
*
* @param create <code>true</code> to create a new session for this request if necessary; <code>false</code> to
* return <code>null</code> if there's no current session
*
* @return the <code>HttpSession</code> associated with this request or <code>null</code> if <code>create</code> is
* <code>false</code> and the request has no valid session
*
* @see #getSession()
*/
HttpSession getSession(boolean create);
/**
* Returns the current session associated with this request, or if the request does not have a session, creates one.
*
* @return the <code>HttpSession</code> associated with this request
*
* @see #getSession(boolean)
*/
HttpSession getSession();
/**
* Changes the session ID of the session associated with this request. This method does not create a new session
* object it only changes the ID of the current session.
*
* @return the new session ID allocated to the session
*
* @see HttpSessionIdListener
*
* @since Servlet 3.1
*/
String changeSessionId();
/**
* Checks whether the requested session ID is still valid.
*
* @return <code>true</code> if this request has an id for a valid session in the current session context;
* <code>false</code> otherwise
*
* @see #getRequestedSessionId
* @see #getSession
*/
boolean isRequestedSessionIdValid();
/**
* Checks whether the requested session ID came in as a cookie.
*
* @return <code>true</code> if the session ID came in as a cookie; otherwise, <code>false</code>
*
* @see #getSession
*/
boolean isRequestedSessionIdFromCookie();
/**
* Checks whether the requested session ID came in as part of the request URL.
*
* @return <code>true</code> if the session ID came in as part of a URL; otherwise, <code>false</code>
*
* @see #getSession
*/
boolean isRequestedSessionIdFromURL();
/**
* Triggers the same authentication process as would be triggered if the request is for a resource that is protected
* by a security constraint.
*
* @param response The response to use to return any authentication challenge
*
* @return <code>true</code> if the user is successfully authenticated and <code>false</code> if not
*
* @throws IOException if the authentication process attempted to read from the request or write to the
* response and an I/O error occurred
* @throws IllegalStateException if the authentication process attempted to write to the response after it had been
* committed
* @throws ServletException if the authentication failed and the caller is expected to handle the failure
*
* @since Servlet 3.0
*/
boolean authenticate(HttpServletResponse response) throws IOException, ServletException;
/**
* Authenticate the provided user name and password and then associated the authenticated user with the request.
*
* @param username The user name to authenticate
* @param password The password to use to authenticate the user
*
* @throws ServletException If any of {@link #getRemoteUser()}, {@link #getUserPrincipal()} or
* {@link #getAuthType()} are non-null, if the configured authenticator does not
* support user name and password authentication or if the authentication fails
*
* @since Servlet 3.0
*/
void login(String username, String password) throws ServletException;
/**
* Removes any authenticated user from the request.
*
* @throws ServletException If the logout fails
*
* @since Servlet 3.0
*/
void logout() throws ServletException;
/**
* Return a collection of all uploaded Parts.
*
* @return A collection of all uploaded Parts.
*
* @throws IOException if an I/O error occurs
* @throws IllegalStateException if size limits are exceeded or no multipart configuration is provided
* @throws ServletException if the request is not multipart/form-data
*
* @since Servlet 3.0
*/
Collection<Part> getParts() throws IOException, ServletException;
/**
* Gets the named Part or null if the Part does not exist. Triggers upload of all Parts.
*
* @param name The name of the Part to obtain
*
* @return The named Part or null if the Part does not exist
*
* @throws IOException if an I/O error occurs
* @throws IllegalStateException if size limits are exceeded
* @throws ServletException if the request is not multipart/form-data
*
* @since Servlet 3.0
*/
Part getPart(String name) throws IOException, ServletException;
/**
* Start the HTTP upgrade process and create and instance of the provided protocol handler class. The connection
* will be passed this instance once the current request/response pair has completed processing. Calling this method
* sets the response status to {@link HttpServletResponse#SC_SWITCHING_PROTOCOLS}.
*
* @param <T> The type of the upgrade handler
* @param httpUpgradeHandlerClass The class that implements the upgrade handler
*
* @return A newly created instance of the specified upgrade handler type
*
* @throws IOException if an I/O error occurred during the upgrade
* @throws ServletException if the given httpUpgradeHandlerClass fails to be instantiated
*
* @since Servlet 3.1
*/
<T extends HttpUpgradeHandler> T upgrade(Class<T> httpUpgradeHandlerClass)
throws IOException, ServletException;
/**
* Obtain a Map of the trailer fields that is not backed by the request object.
*
* @return A Map of the received trailer fields with all keys lower case or an empty Map if no trailers are present
*
* @since Servlet 4.0
*/
default Map<String,String> getTrailerFields() {
return Collections.emptyMap();
}
/**
* Are trailer fields ready to be read (there may still be no trailers to read). This method always returns
* {@code true} if the underlying protocol does not support trailer fields. Otherwise, {@code true} is returned once
* all of the following are true:
* <ul>
* <li>The application has ready all the request data and an EOF has been received or the content-length is
* zero</li>
* <li>All trailer fields, if any, have been received</li>
* </ul>
*
* @return {@code true} if trailers are ready to be read
*
* @since Servlet 4.0
*/
default boolean isTrailerFieldsReady() {
return true;
}
}