org.jboss.spec.javax.servlet/jboss-servlet-api_4.0_spec/1.0.0.Final : javax/servlet/http/HttpServletResponse.java

HttpServletResponse
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package javax.servlet.http;

import java.io.IOException;
import java.util.Collection;
import java.util.Map;
import java.util.function.Supplier;
import javax.servlet.ServletResponse;

Extends the ServletResponse interface to provide HTTP-specific functionality in sending a response. For example, it has methods to access HTTP headers and cookies. The servlet container creates an HttpServletResponse object
and passes it as an argument to the servlet's service methods
(doGet, doPost, etc).
Author: 	Various
See Also: ServletResponse/**
 *
 * Extends the {@link ServletResponse} interface to provide HTTP-specific
 * functionality in sending a response.  For example, it has methods
 * to access HTTP headers and cookies.
 *
 * <p>The servlet container creates an <code>HttpServletResponse</code> object
 * and passes it as an argument to the servlet's service methods
 * (<code>doGet</code>, <code>doPost</code>, etc).
 *
 * 
 * @author	Various
 *
 * @see		javax.servlet.ServletResponse
 *
 */
public interface HttpServletResponse extends ServletResponse {

    Adds the specified cookie to the response.  This method can be called
multiple times to set more than one cookie.
Params: cookie – the Cookie to return to the client/**
     * Adds the specified cookie to the response.  This method can be called
     * multiple times to set more than one cookie.
     *
     * @param cookie the Cookie to return to the client
     *
     */
    public void addCookie(Cookie cookie);

    Returns a boolean indicating whether the named response header 
has already been set.
Params: name – 	the header name
Returns: 		true if the named response header 
		has already been set; 
			false otherwise/**
     * Returns a boolean indicating whether the named response header 
     * has already been set.
     * 
     * @param	name	the header name
     * @return		<code>true</code> if the named response header 
     *			has already been set; 
     * 			<code>false</code> otherwise
     */
    public boolean containsHeader(String name);

    Encodes the specified URL by including the session ID,
or, if encoding is not needed, returns the URL unchanged.
The implementation of this method includes the logic to
determine whether the session ID needs to be encoded in the URL.
For example, if the browser supports cookies, or session
tracking is turned off, URL encoding is unnecessary.
For robust session tracking, all URLs emitted by a servlet 
should be run through this
method.  Otherwise, URL rewriting cannot be used with browsers
which do not support cookies.
If the URL is relative, it is always relative to the current
HttpServletRequest.
Params: url – 	the url to be encoded.
Throws: IllegalArgumentException – if the url is not valid
Returns: 		the encoded URL if encoding is needed;
			the unchanged URL otherwise./**
     * Encodes the specified URL by including the session ID,
     * or, if encoding is not needed, returns the URL unchanged.
     * The implementation of this method includes the logic to
     * determine whether the session ID needs to be encoded in the URL.
     * For example, if the browser supports cookies, or session
     * tracking is turned off, URL encoding is unnecessary.
     * 
     * <p>For robust session tracking, all URLs emitted by a servlet 
     * should be run through this
     * method.  Otherwise, URL rewriting cannot be used with browsers
     * which do not support cookies.
     *
     * <p>If the URL is relative, it is always relative to the current
     * HttpServletRequest.
     *
     * @param	url	the url to be encoded.
     * @return		the encoded URL if encoding is needed;
     * 			the unchanged URL otherwise.
     * @exception IllegalArgumentException if the url is not valid
     */
    public String encodeURL(String url);

    Encodes the specified URL for use in the
sendRedirect method or, if encoding is not needed,
returns the URL unchanged.  The implementation of this method
includes the logic to determine whether the session ID
needs to be encoded in the URL.  For example, if the browser supports
cookies, or session tracking is turned off, URL encoding is
unnecessary.  Because the rules for making this determination can
differ from those used to decide whether to
encode a normal link, this method is separated from the
encodeURL method.
All URLs sent to the HttpServletResponse.sendRedirect
method should be run through this method.  Otherwise, URL
rewriting cannot be used with browsers which do not support
cookies.
If the URL is relative, it is always relative to the current
HttpServletRequest.
Params: url – 	the url to be encoded.
Throws: IllegalArgumentException – if the url is not valid
See Also: sendRedirect
encodeUrl
Returns: 		the encoded URL if encoding is needed;
			the unchanged URL otherwise./**
     * Encodes the specified URL for use in the
     * <code>sendRedirect</code> method or, if encoding is not needed,
     * returns the URL unchanged.  The implementation of this method
     * includes the logic to determine whether the session ID
     * needs to be encoded in the URL.  For example, if the browser supports
     * cookies, or session tracking is turned off, URL encoding is
     * unnecessary.  Because the rules for making this determination can
     * differ from those used to decide whether to
     * encode a normal link, this method is separated from the
     * <code>encodeURL</code> method.
     * 
     * <p>All URLs sent to the <code>HttpServletResponse.sendRedirect</code>
     * method should be run through this method.  Otherwise, URL
     * rewriting cannot be used with browsers which do not support
     * cookies.
     *
     * <p>If the URL is relative, it is always relative to the current
     * HttpServletRequest.
     *
     * @param	url	the url to be encoded.
     * @return		the encoded URL if encoding is needed;
     * 			the unchanged URL otherwise.
     * @exception IllegalArgumentException if the url is not valid
     *
     * @see #sendRedirect
     * @see #encodeUrl
     */
    public String encodeRedirectURL(String url);

    Params: url – 	the url to be encoded.
Throws: IllegalArgumentException – if the url is not valid
Deprecated: 	As of version 2.1, use encodeURL(String url) instead
Returns: 		the encoded URL if encoding is needed; 
			the unchanged URL otherwise./**
     * @deprecated	As of version 2.1, use encodeURL(String url) instead
     *
     * @param	url	the url to be encoded.
     * @return		the encoded URL if encoding is needed; 
     * 			the unchanged URL otherwise.
     * @exception IllegalArgumentException if the url is not valid
     */
    @Deprecated
    public String encodeUrl(String url);
    
    Params: url – 	the url to be encoded.
Throws: IllegalArgumentException – if the url is not valid
Deprecated: 	As of version 2.1, use 
		encodeRedirectURL(String url) instead
Returns: 		the encoded URL if encoding is needed; 
			the unchanged URL otherwise./**
     * @deprecated	As of version 2.1, use 
     *			encodeRedirectURL(String url) instead
     *
     * @param	url	the url to be encoded.
     * @return		the encoded URL if encoding is needed; 
     * 			the unchanged URL otherwise.
     * @exception IllegalArgumentException if the url is not valid
     */
    @Deprecated
    public String encodeRedirectUrl(String url);

    Sends an error response to the client using the specified
status and clears the buffer.  The server defaults to creating
the response to look like an HTML-formatted server error page
containing the specified message, setting the content type to
"text/html".  The caller is not responsible for
escaping or re-encoding the message to ensure it is safe with
respect to the current response encoding and content type.  This
aspect of safety is the responsibility of the container, as it is
generating the error page containing the message.  The server
will preserve cookies and may clear or update any headers needed
to serve the error page as a valid response.
If an error-page declaration has been made for the web
application corresponding to the status code passed in, it will
be served back in preference to the suggested msg parameter and
the msg parameter will be ignored.
If the response has already been committed, this method throws 
an IllegalStateException.
After using this method, the response should be considered
to be committed and should not be written to.
Params: sc – 	the error status code
msg – 	the descriptive message
Throws: IOException – 	If an input or output exception occurs
IllegalStateException – 	If the response was committed/**
     * <p>Sends an error response to the client using the specified
     * status and clears the buffer.  The server defaults to creating
     * the response to look like an HTML-formatted server error page
     * containing the specified message, setting the content type to
     * "text/html".  The caller is <strong>not</strong> responsible for
     * escaping or re-encoding the message to ensure it is safe with
     * respect to the current response encoding and content type.  This
     * aspect of safety is the responsibility of the container, as it is
     * generating the error page containing the message.  The server
     * will preserve cookies and may clear or update any headers needed
     * to serve the error page as a valid response.</p>
     *
     * <p>If an error-page declaration has been made for the web
     * application corresponding to the status code passed in, it will
     * be served back in preference to the suggested msg parameter and
     * the msg parameter will be ignored.</p>
     *
     * <p>If the response has already been committed, this method throws 
     * an IllegalStateException.
     * After using this method, the response should be considered
     * to be committed and should not be written to.
     *
     * @param	sc	the error status code
     * @param	msg	the descriptive message
     * @exception	IOException	If an input or output exception occurs
     * @exception	IllegalStateException	If the response was committed
     */
    public void sendError(int sc, String msg) throws IOException;

    Sends an error response to the client using the specified status
code and clears the buffer.
The server will preserve cookies and may clear or
update any headers needed to serve the error page as a valid response.
If an error-page declaration has been made for the web application
corresponding to the status code passed in, it will be served back
the error page
If the response has already been committed, this method throws 
an IllegalStateException.
After using this method, the response should be considered
to be committed and should not be written to.
Params: sc – 	the error status code
Throws: IOException – 	If an input or output exception occurs
IllegalStateException – 	If the response was committed
					before this method call/**
     * Sends an error response to the client using the specified status
     * code and clears the buffer.
     * 
     * The server will preserve cookies and may clear or
     * update any headers needed to serve the error page as a valid response.
     *
     * If an error-page declaration has been made for the web application
     * corresponding to the status code passed in, it will be served back
     * the error page
     * 
     * <p>If the response has already been committed, this method throws 
     * an IllegalStateException.
     * After using this method, the response should be considered
     * to be committed and should not be written to.
     *
     * @param	sc	the error status code
     * @exception	IOException	If an input or output exception occurs
     * @exception	IllegalStateException	If the response was committed
     *						before this method call
     */
    public void sendError(int sc) throws IOException;

    Sends a temporary redirect response to the client using the specified redirect location URL and clears the buffer. The buffer will be replaced with the data set by this method. Calling this method sets the status code to SC_FOUND 302 (Found). This method can accept relative URLs;the servlet container must convert the relative URL to an absolute URL before sending the response to the client. If the location is relative without a leading '/' the container interprets it as relative to the current request URI. If the location is relative with a leading '/' the container interprets it as relative to the servlet container root. If the location is relative with two leading '/' the container interprets it as a network-path reference (see 
RFC 3986: Uniform Resource Identifier (URI): Generic Syntax, section 4.2
"Relative Reference").
If the response has already been committed, this method throws 
an IllegalStateException.
After using this method, the response should be considered
to be committed and should not be written to.
Params: location – 	the redirect location URL
Throws: IOException – 	If an input or output exception occurs
IllegalStateException – 	If the response was committed or
             if a partial URL is given and cannot be converted into a valid URL/**
     * Sends a temporary redirect response to the client using the
     * specified redirect location URL and clears the buffer. The buffer will
     * be replaced with the data set by this method. Calling this method sets the
     * status code to {@link #SC_FOUND} 302 (Found).
     * This method can accept relative URLs;the servlet container must convert
     * the relative URL to an absolute URL
     * before sending the response to the client. If the location is relative 
     * without a leading '/' the container interprets it as relative to
     * the current request URI. If the location is relative with a leading
     * '/' the container interprets it as relative to the servlet container root.
     * If the location is relative with two leading '/' the container interprets
     * it as a network-path reference (see
     * <a href="http://www.ietf.org/rfc/rfc3986.txt">
     * RFC 3986: Uniform Resource Identifier (URI): Generic Syntax</a>, section 4.2
     * &quot;Relative Reference&quot;).
     *
     * <p>If the response has already been committed, this method throws 
     * an IllegalStateException.
     * After using this method, the response should be considered
     * to be committed and should not be written to.
     *
     * @param		location	the redirect location URL
     * @exception	IOException	If an input or output exception occurs
     * @exception	IllegalStateException	If the response was committed or
     *              if a partial URL is given and cannot be converted into a valid URL
     */
    public void sendRedirect(String location) throws IOException;
    
    Sets a response header with the given name and
date-value.  The date is specified in terms of
milliseconds since the epoch.  If the header had already
been set, the new value overwrites the previous one.  The
containsHeader method can be used to test for the
presence of a header before setting its value.
Params: name – 	the name of the header to set
date – 	the assigned date value
See Also: containsHeader
addDateHeader/**
     * 
     * Sets a response header with the given name and
     * date-value.  The date is specified in terms of
     * milliseconds since the epoch.  If the header had already
     * been set, the new value overwrites the previous one.  The
     * <code>containsHeader</code> method can be used to test for the
     * presence of a header before setting its value.
     * 
     * @param	name	the name of the header to set
     * @param	date	the assigned date value
     * 
     * @see #containsHeader
     * @see #addDateHeader
     */
    public void setDateHeader(String name, long date);
    
    Adds a response header with the given name and
date-value.  The date is specified in terms of
milliseconds since the epoch.  This method allows response headers 
to have multiple values.
Params: name – 	the name of the header to set
date – 	the additional date value
See Also: setDateHeader/**
     * 
     * Adds a response header with the given name and
     * date-value.  The date is specified in terms of
     * milliseconds since the epoch.  This method allows response headers 
     * to have multiple values.
     * 
     * @param	name	the name of the header to set
     * @param	date	the additional date value
     * 
     * @see #setDateHeader
     */
    public void addDateHeader(String name, long date);
    
    Sets a response header with the given name and value.
If the header had already been set, the new value overwrites the
previous one.  The containsHeader method can be
used to test for the presence of a header before setting its
value.
Params: name – 	the name of the header
value – 	the header value  If it contains octet string,
	it should be encoded according to RFC 2047
	(http://www.ietf.org/rfc/rfc2047.txt)
See Also: containsHeader
addHeader/**
     *
     * Sets a response header with the given name and value.
     * If the header had already been set, the new value overwrites the
     * previous one.  The <code>containsHeader</code> method can be
     * used to test for the presence of a header before setting its
     * value.
     * 
     * @param	name	the name of the header
     * @param	value	the header value  If it contains octet string,
     *		it should be encoded according to RFC 2047
     *		(http://www.ietf.org/rfc/rfc2047.txt)
     *
     * @see #containsHeader
     * @see #addHeader
     */
    public void setHeader(String name, String value);
    
    Adds a response header with the given name and value.
This method allows response headers to have multiple values.
Params: name – 	the name of the header
value – 	the additional header value   If it contains
	octet string, it should be encoded
	according to RFC 2047
	(http://www.ietf.org/rfc/rfc2047.txt)
See Also: setHeader/**
     * Adds a response header with the given name and value.
     * This method allows response headers to have multiple values.
     * 
     * @param	name	the name of the header
     * @param	value	the additional header value   If it contains
     *		octet string, it should be encoded
     *		according to RFC 2047
     *		(http://www.ietf.org/rfc/rfc2047.txt)
     *
     * @see #setHeader
     */
    public void addHeader(String name, String value);

    Sets a response header with the given name and
integer value.  If the header had already been set, the new value
overwrites the previous one.  The containsHeader
method can be used to test for the presence of a header before
setting its value.
Params: name – 	the name of the header
value – 	the assigned integer value
See Also: containsHeader
addIntHeader/**
     * Sets a response header with the given name and
     * integer value.  If the header had already been set, the new value
     * overwrites the previous one.  The <code>containsHeader</code>
     * method can be used to test for the presence of a header before
     * setting its value.
     *
     * @param	name	the name of the header
     * @param	value	the assigned integer value
     *
     * @see #containsHeader
     * @see #addIntHeader
     */
    public void setIntHeader(String name, int value);

    Adds a response header with the given name and
integer value.  This method allows response headers to have multiple
values.
Params: name – 	the name of the header
value – 	the assigned integer value
See Also: setIntHeader/**
     * Adds a response header with the given name and
     * integer value.  This method allows response headers to have multiple
     * values.
     *
     * @param	name	the name of the header
     * @param	value	the assigned integer value
     *
     * @see #setIntHeader
     */
    public void addIntHeader(String name, int value);

    Sets the status code for this response. 
This method is used to set the return status code when there is
no error (for example, for the SC_OK or SC_MOVED_TEMPORARILY status
codes).
If this method is used to set an error code, then the container's error page mechanism will not be triggered. If there is an error and the caller wishes to invoke an error page defined in the web application, then sendError must be used instead. 
This method preserves any cookies and other response headers. 
Valid status codes are those in the 2XX, 3XX, 4XX, and 5XX ranges.
Other status codes are treated as container specific.
Params: sc – 	the status code
See Also: sendError/**
     * Sets the status code for this response. 
     *
     * <p>This method is used to set the return status code when there is
     * no error (for example, for the SC_OK or SC_MOVED_TEMPORARILY status
     * codes).
     *
     * <p>If this method is used to set an error code, then the container's
     * error page mechanism will not be triggered. If there is an error and
     * the caller wishes to invoke an error page defined in the web
     * application, then {@link #sendError} must be used instead.
     *
     * <p>This method preserves any cookies and other response headers. 
     *
     * <p>Valid status codes are those in the 2XX, 3XX, 4XX, and 5XX ranges.
     * Other status codes are treated as container specific.
     *
     * @param	sc	the status code
     *
     * @see #sendError
     */
    public void setStatus(int sc);
  

    Params: sc – 	the status code
sm – 	the status message
Deprecated: As of version 2.1, due to ambiguous meaning of the 
message parameter. To set a status code 
use setStatus(int), to send an error with a description
use sendError(int, String).
Sets the status code and message for this response./**
     * @deprecated As of version 2.1, due to ambiguous meaning of the 
     * message parameter. To set a status code 
     * use <code>setStatus(int)</code>, to send an error with a description
     * use <code>sendError(int, String)</code>.
     *
     * Sets the status code and message for this response.
     * 
     * @param	sc	the status code
     * @param	sm	the status message
     */
    @Deprecated
    public void setStatus(int sc, String sm);

    Gets the current status code of this response.
Returns: the current status code of this response
Since: Servlet 3.0/**
     * Gets the current status code of this response.
     *
     * @return the current status code of this response
     *
     * @since Servlet 3.0
     */
    public int getStatus();

    Gets the value of the response header with the given name.
If a response header with the given name exists and contains
multiple values, the value that was added first will be returned.
This method considers only response headers set or added via setHeader, addHeader, setDateHeader, addDateHeader, setIntHeader, or addIntHeader, respectively. 
Params: name – the name of the response header whose value to return
Returns: the value of the response header with the given name,
or null if no header with the given name has been set
on this response
Since: Servlet 3.0/**
     * Gets the value of the response header with the given name.
     * 
     * <p>If a response header with the given name exists and contains
     * multiple values, the value that was added first will be returned.
     *
     * <p>This method considers only response headers set or added via
     * {@link #setHeader}, {@link #addHeader}, {@link #setDateHeader},
     * {@link #addDateHeader}, {@link #setIntHeader}, or
     * {@link #addIntHeader}, respectively.
     *
     * @param name the name of the response header whose value to return
     *
     * @return the value of the response header with the given name,
     * or <tt>null</tt> if no header with the given name has been set
     * on this response
     *
     * @since Servlet 3.0
     */
    public String getHeader(String name); 

    Gets the values of the response header with the given name.
This method considers only response headers set or added via setHeader, addHeader, setDateHeader, addDateHeader, setIntHeader, or addIntHeader, respectively. 
Any changes to the returned Collection must not 
affect this HttpServletResponse.
Params: name – the name of the response header whose values to return
Returns: a (possibly empty) Collection of the values
of the response header with the given name
Since: Servlet 3.0/**
     * Gets the values of the response header with the given name.
     *
     * <p>This method considers only response headers set or added via
     * {@link #setHeader}, {@link #addHeader}, {@link #setDateHeader},
     * {@link #addDateHeader}, {@link #setIntHeader}, or
     * {@link #addIntHeader}, respectively.
     *
     * <p>Any changes to the returned <code>Collection</code> must not 
     * affect this <code>HttpServletResponse</code>.
     *
     * @param name the name of the response header whose values to return
     *
     * @return a (possibly empty) <code>Collection</code> of the values
     * of the response header with the given name
     *
     * @since Servlet 3.0
     */			
    public Collection<String> getHeaders(String name); 
    
    Gets the names of the headers of this response.
This method considers only response headers set or added via setHeader, addHeader, setDateHeader, addDateHeader, setIntHeader, or addIntHeader, respectively. 
Any changes to the returned Collection must not 
affect this HttpServletResponse.
Returns: a (possibly empty) Collection of the names
of the headers of this response
Since: Servlet 3.0/**
     * Gets the names of the headers of this response.
     *
     * <p>This method considers only response headers set or added via
     * {@link #setHeader}, {@link #addHeader}, {@link #setDateHeader},
     * {@link #addDateHeader}, {@link #setIntHeader}, or
     * {@link #addIntHeader}, respectively.
     *
     * <p>Any changes to the returned <code>Collection</code> must not 
     * affect this <code>HttpServletResponse</code>.
     *
     * @return a (possibly empty) <code>Collection</code> of the names
     * of the headers of this response
     *
     * @since Servlet 3.0
     */
    public Collection<String> getHeaderNames();

    Sets the supplier of trailer headers.
The trailer header field value is defined as a comma-separated list
(see Section 3.2.2 and Section 4.1.2 of RFC 7230).
The supplier will be called within the scope of whatever thread/call
causes the response content to be completed. Typically this will
be any thread calling close() on the output stream or writer.
The trailers that run afoul of the provisions of section 4.1.2 of
RFC 7230 are ignored.
The RFC requires the name of every key that is to be in the
supplied Map is included in the comma separated list that is the value
of the "Trailer" response header.  The application is responsible for
ensuring this requirement is met.  Failure to do so may lead to
interoperability failures.
Params: supplier – the supplier of trailer headers
Throws: IllegalStateException – if it is invoked after the response has
        has been committed,
        or the trailer is not supported in the request, for instance,
        the underlying protocol is HTTP 1.0, or the response is not
        in chunked encoding in HTTP 1.1.
Implementation Requirements: 
The default implementation is a no-op.
Since: Servlet 4.0/**
     * Sets the supplier of trailer headers.
     *
     * <p>The trailer header field value is defined as a comma-separated list
     * (see Section 3.2.2 and Section 4.1.2 of RFC 7230).</p>
     *
     * <p>The supplier will be called within the scope of whatever thread/call
     * causes the response content to be completed. Typically this will
     * be any thread calling close() on the output stream or writer.</p>
     *
     * <p>The trailers that run afoul of the provisions of section 4.1.2 of
     * RFC 7230 are ignored.</p>
     *
     * <p>The RFC requires the name of every key that is to be in the
     * supplied Map is included in the comma separated list that is the value
     * of the "Trailer" response header.  The application is responsible for
     * ensuring this requirement is met.  Failure to do so may lead to
     * interoperability failures.</p>
     *
     * @implSpec
     * The default implementation is a no-op.
     *
     * @param supplier the supplier of trailer headers
     *
     * @exception IllegalStateException if it is invoked after the response has
     *         has been committed,
     *         or the trailer is not supported in the request, for instance,
     *         the underlying protocol is HTTP 1.0, or the response is not
     *         in chunked encoding in HTTP 1.1.
     *
     * @since Servlet 4.0
     */
    default public void setTrailerFields(Supplier<Map<String, String>> supplier) {
    }

    Gets the supplier of trailer headers.
Implementation Requirements: 
The default implememtation return null.
Returns: Supplier of trailer headers
Since: Servlet 4.0/**
     * Gets the supplier of trailer headers.
     *
     * @implSpec
     * The default implememtation return null.
     *
     * @return <code>Supplier</code> of trailer headers
     * 
     * @since Servlet 4.0
     */
    default public Supplier<Map<String, String>> getTrailerFields() {
        return null;
    }


    /*
     * Server status codes; see RFC 2068.
     */

    Status code (100) indicating the client can continue.
/**
     * Status code (100) indicating the client can continue.
     */
    public static final int SC_CONTINUE = 100;

    Status code (101) indicating the server is switching protocols
according to Upgrade header.
/**
     * Status code (101) indicating the server is switching protocols
     * according to Upgrade header.
     */
    public static final int SC_SWITCHING_PROTOCOLS = 101;

    Status code (200) indicating the request succeeded normally.
/**
     * Status code (200) indicating the request succeeded normally.
     */
    public static final int SC_OK = 200;

    Status code (201) indicating the request succeeded and created
a new resource on the server.
/**
     * Status code (201) indicating the request succeeded and created
     * a new resource on the server.
     */
    public static final int SC_CREATED = 201;

    Status code (202) indicating that a request was accepted for
processing, but was not completed.
/**
     * Status code (202) indicating that a request was accepted for
     * processing, but was not completed.
     */
    public static final int SC_ACCEPTED = 202;

    Status code (203) indicating that the meta information presented
by the client did not originate from the server.
/**
     * Status code (203) indicating that the meta information presented
     * by the client did not originate from the server.
     */
    public static final int SC_NON_AUTHORITATIVE_INFORMATION = 203;

    Status code (204) indicating that the request succeeded but that
there was no new information to return.
/**
     * Status code (204) indicating that the request succeeded but that
     * there was no new information to return.
     */
    public static final int SC_NO_CONTENT = 204;

    Status code (205) indicating that the agent SHOULD reset
the document view which caused the request to be sent.
/**
     * Status code (205) indicating that the agent <em>SHOULD</em> reset
     * the document view which caused the request to be sent.
     */
    public static final int SC_RESET_CONTENT = 205;

    Status code (206) indicating that the server has fulfilled
the partial GET request for the resource.
/**
     * Status code (206) indicating that the server has fulfilled
     * the partial GET request for the resource.
     */
    public static final int SC_PARTIAL_CONTENT = 206;

    Status code (300) indicating that the requested resource
corresponds to any one of a set of representations, each with
its own specific location.
/**
     * Status code (300) indicating that the requested resource
     * corresponds to any one of a set of representations, each with
     * its own specific location.
     */
    public static final int SC_MULTIPLE_CHOICES = 300;

    Status code (301) indicating that the resource has permanently
moved to a new location, and that future references should use a
new URI with their requests.
/**
     * Status code (301) indicating that the resource has permanently
     * moved to a new location, and that future references should use a
     * new URI with their requests.
     */
    public static final int SC_MOVED_PERMANENTLY = 301;

    Status code (302) indicating that the resource has temporarily
moved to another location, but that future references should
still use the original URI to access the resource.
This definition is being retained for backwards compatibility.
SC_FOUND is now the preferred definition.
/**
     * Status code (302) indicating that the resource has temporarily
     * moved to another location, but that future references should
     * still use the original URI to access the resource.
     *
     * This definition is being retained for backwards compatibility.
     * SC_FOUND is now the preferred definition.
     */
    public static final int SC_MOVED_TEMPORARILY = 302;

    Status code (302) indicating that the resource reside
temporarily under a different URI. Since the redirection might
be altered on occasion, the client should continue to use the
Request-URI for future requests.(HTTP/1.1) To represent the
status code (302), it is recommended to use this variable.
/**
    * Status code (302) indicating that the resource reside
    * temporarily under a different URI. Since the redirection might
    * be altered on occasion, the client should continue to use the
    * Request-URI for future requests.(HTTP/1.1) To represent the
    * status code (302), it is recommended to use this variable.
    */
    public static final int SC_FOUND = 302;

    Status code (303) indicating that the response to the request
can be found under a different URI.
/**
     * Status code (303) indicating that the response to the request
     * can be found under a different URI.
     */
    public static final int SC_SEE_OTHER = 303;

    Status code (304) indicating that a conditional GET operation
found that the resource was available and not modified.
/**
     * Status code (304) indicating that a conditional GET operation
     * found that the resource was available and not modified.
     */
    public static final int SC_NOT_MODIFIED = 304;

    Status code (305) indicating that the requested resource
MUST be accessed through the proxy given by the
Location field.
/**
     * Status code (305) indicating that the requested resource
     * <em>MUST</em> be accessed through the proxy given by the
     * <code><em>Location</em></code> field.
     */
    public static final int SC_USE_PROXY = 305;

     Status code (307) indicating that the requested resource 
resides temporarily under a different URI. The temporary URI
SHOULD be given by the Location 
field in the response.
/**
     * Status code (307) indicating that the requested resource 
     * resides temporarily under a different URI. The temporary URI
     * <em>SHOULD</em> be given by the <code><em>Location</em></code> 
     * field in the response.
     */
    public static final int SC_TEMPORARY_REDIRECT = 307;

    Status code (400) indicating the request sent by the client was
syntactically incorrect.
/**
     * Status code (400) indicating the request sent by the client was
     * syntactically incorrect.
     */
    public static final int SC_BAD_REQUEST = 400;

    Status code (401) indicating that the request requires HTTP
authentication.
/**
     * Status code (401) indicating that the request requires HTTP
     * authentication.
     */
    public static final int SC_UNAUTHORIZED = 401;

    Status code (402) reserved for future use.
/**
     * Status code (402) reserved for future use.
     */
    public static final int SC_PAYMENT_REQUIRED = 402;

    Status code (403) indicating the server understood the request
but refused to fulfill it.
/**
     * Status code (403) indicating the server understood the request
     * but refused to fulfill it.
     */
    public static final int SC_FORBIDDEN = 403;

    Status code (404) indicating that the requested resource is not
available.
/**
     * Status code (404) indicating that the requested resource is not
     * available.
     */
    public static final int SC_NOT_FOUND = 404;

    Status code (405) indicating that the method specified in the
Request-Line is not allowed for the resource
identified by the Request-URI.
/**
     * Status code (405) indicating that the method specified in the
     * <code><em>Request-Line</em></code> is not allowed for the resource
     * identified by the <code><em>Request-URI</em></code>.
     */
    public static final int SC_METHOD_NOT_ALLOWED = 405;

    Status code (406) indicating that the resource identified by the
request is only capable of generating response entities which have
content characteristics not acceptable according to the accept
headers sent in the request.
/**
     * Status code (406) indicating that the resource identified by the
     * request is only capable of generating response entities which have
     * content characteristics not acceptable according to the accept
     * headers sent in the request.
     */
    public static final int SC_NOT_ACCEPTABLE = 406;

    Status code (407) indicating that the client MUST first
authenticate itself with the proxy.
/**
     * Status code (407) indicating that the client <em>MUST</em> first
     * authenticate itself with the proxy.
     */
    public static final int SC_PROXY_AUTHENTICATION_REQUIRED = 407;

    Status code (408) indicating that the client did not produce a
request within the time that the server was prepared to wait.
/**
     * Status code (408) indicating that the client did not produce a
     * request within the time that the server was prepared to wait.
     */
    public static final int SC_REQUEST_TIMEOUT = 408;

    Status code (409) indicating that the request could not be
completed due to a conflict with the current state of the
resource.
/**
     * Status code (409) indicating that the request could not be
     * completed due to a conflict with the current state of the
     * resource.
     */
    public static final int SC_CONFLICT = 409;

    Status code (410) indicating that the resource is no longer
available at the server and no forwarding address is known.
This condition SHOULD be considered permanent.
/**
     * Status code (410) indicating that the resource is no longer
     * available at the server and no forwarding address is known.
     * This condition <em>SHOULD</em> be considered permanent.
     */
    public static final int SC_GONE = 410;

    Status code (411) indicating that the request cannot be handled
without a defined Content-Length.
/**
     * Status code (411) indicating that the request cannot be handled
     * without a defined <code><em>Content-Length</em></code>.
     */
    public static final int SC_LENGTH_REQUIRED = 411;

    Status code (412) indicating that the precondition given in one
or more of the request-header fields evaluated to false when it
was tested on the server.
/**
     * Status code (412) indicating that the precondition given in one
     * or more of the request-header fields evaluated to false when it
     * was tested on the server.
     */
    public static final int SC_PRECONDITION_FAILED = 412;

    Status code (413) indicating that the server is refusing to process
the request because the request entity is larger than the server is
willing or able to process.
/**
     * Status code (413) indicating that the server is refusing to process
     * the request because the request entity is larger than the server is
     * willing or able to process.
     */
    public static final int SC_REQUEST_ENTITY_TOO_LARGE = 413;

    Status code (414) indicating that the server is refusing to service
the request because the Request-URI is longer
than the server is willing to interpret.
/**
     * Status code (414) indicating that the server is refusing to service
     * the request because the <code><em>Request-URI</em></code> is longer
     * than the server is willing to interpret.
     */
    public static final int SC_REQUEST_URI_TOO_LONG = 414;

    Status code (415) indicating that the server is refusing to service
the request because the entity of the request is in a format not
supported by the requested resource for the requested method.
/**
     * Status code (415) indicating that the server is refusing to service
     * the request because the entity of the request is in a format not
     * supported by the requested resource for the requested method.
     */
    public static final int SC_UNSUPPORTED_MEDIA_TYPE = 415;

    Status code (416) indicating that the server cannot serve the
requested byte range.
/**
     * Status code (416) indicating that the server cannot serve the
     * requested byte range.
     */
    public static final int SC_REQUESTED_RANGE_NOT_SATISFIABLE = 416;

    Status code (417) indicating that the server could not meet the
expectation given in the Expect request header.
/**
     * Status code (417) indicating that the server could not meet the
     * expectation given in the Expect request header.
     */
    public static final int SC_EXPECTATION_FAILED = 417;

    Status code (500) indicating an error inside the HTTP server
which prevented it from fulfilling the request.
/**
     * Status code (500) indicating an error inside the HTTP server
     * which prevented it from fulfilling the request.
     */
    public static final int SC_INTERNAL_SERVER_ERROR = 500;

    Status code (501) indicating the HTTP server does not support
the functionality needed to fulfill the request.
/**
     * Status code (501) indicating the HTTP server does not support
     * the functionality needed to fulfill the request.
     */
    public static final int SC_NOT_IMPLEMENTED = 501;

    Status code (502) indicating that the HTTP server received an
invalid response from a server it consulted when acting as a
proxy or gateway.
/**
     * Status code (502) indicating that the HTTP server received an
     * invalid response from a server it consulted when acting as a
     * proxy or gateway.
     */
    public static final int SC_BAD_GATEWAY = 502;

    Status code (503) indicating that the HTTP server is
temporarily overloaded, and unable to handle the request.
/**
     * Status code (503) indicating that the HTTP server is
     * temporarily overloaded, and unable to handle the request.
     */
    public static final int SC_SERVICE_UNAVAILABLE = 503;

    Status code (504) indicating that the server did not receive
a timely response from the upstream server while acting as
a gateway or proxy.
/**
     * Status code (504) indicating that the server did not receive
     * a timely response from the upstream server while acting as
     * a gateway or proxy.
     */
    public static final int SC_GATEWAY_TIMEOUT = 504;

    Status code (505) indicating that the server does not support
or refuses to support the HTTP protocol version that was used
in the request message.
/**
     * Status code (505) indicating that the server does not support
     * or refuses to support the HTTP protocol version that was used
     * in the request message.
     */
    public static final int SC_HTTP_VERSION_NOT_SUPPORTED = 505;
}
Params:	name – the header name
Returns:	`true` if the named response header has already been set; `false` otherwise
Params:	url – the url to be encoded.
Throws:	IllegalArgumentException – if the url is not valid
Returns:	the encoded URL if encoding is needed; the unchanged URL otherwise.
Params:	sc – the error status code msg – the descriptive message
Throws:	IOException – If an input or output exception occurs IllegalStateException – If the response was committed
Params:	sc – the error status code
Throws:	IOException – If an input or output exception occurs IllegalStateException – If the response was committed before this method call
Params:	location – the redirect location URL
Throws:	IOException – If an input or output exception occurs IllegalStateException – If the response was committed or if a partial URL is given and cannot be converted into a valid URL
Params:	name – the name of the header to set date – the assigned date value
See Also:	containsHeader addDateHeader
Params:	name – the name of the header value – the header value If it contains octet string, it should be encoded according to RFC 2047 (http://www.ietf.org/rfc/rfc2047.txt)
See Also:	containsHeader addHeader
Params:	sc – the status code sm – the status message
Deprecated:	As of version 2.1, due to ambiguous meaning of the message parameter. To set a status code use `setStatus(int)`, to send an error with a description use `sendError(int, String)`. Sets the status code and message for this response.
Returns:	the current status code of this response
Since:	Servlet 3.0
Params:	name – the name of the response header whose value to return
Returns:	the value of the response header with the given name, or `null` if no header with the given name has been set on this response
Since:	Servlet 3.0
Returns:	a (possibly empty) `Collection` of the names of the headers of this response
Since:	Servlet 3.0
Params:	supplier – the supplier of trailer headers
Throws:	IllegalStateException – if it is invoked after the response has has been committed, or the trailer is not supported in the request, for instance, the underlying protocol is HTTP 1.0, or the response is not in chunked encoding in HTTP 1.1.
Implementation Requirements:	The default implementation is a no-op.
Since:	Servlet 4.0
Implementation Requirements:	The default implememtation return null.
Returns:	`Supplier` of trailer headers
Since:	Servlet 4.0
/

org.jboss.spec.javax.servlet/ jboss-servlet-api_4.0_spec/ 1.0.0.Final/ javax/servlet/http/HttpServletResponse.java
