public Interface HttpServletResponse

Status code (202) indicating that a request was accepted for processing, but was not completed.

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 (400) indicating the request sent by the client was syntactically incorrect.

Status code (409) indicating that the request could not be completed due to a conflict with the current state of the resource.

Status code (100) indicating the client can continue.

Status code (201) indicating the request succeeded and created a new resource on the server.

Status code (417) indicating that the server could not meet the expectation given in the Expect request header.

Status code (403) indicating the server understood the request but refused to fulfill it.

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 (504) indicating that the server did not receive a timely response from the upstream server while acting as a gateway or proxy.

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 (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 (500) indicating an error inside the HTTP server which prevented it from fulfilling the request.

Status code (411) indicating that the request cannot be handled without a defined Content-Length.

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 (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 (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 (300) indicating that the requested resource corresponds to any one of a set of representations, each with its own specific location.

Status code (204) indicating that the request succeeded but that there was no new information to return.

Status code (203) indicating that the meta information presented by the client did not originate from the server.

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 (404) indicating that the requested resource is not available.

Status code (501) indicating the HTTP server does not support the functionality needed to fulfill the request.

Status code (304) indicating that a conditional GET operation found that the resource was available and not modified.

Status code (200) indicating the request succeeded normally.

Status code (206) indicating that the server has fulfilled the partial GET request for the resource.

Status code (402) reserved for future use.

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 (407) indicating that the client MUST first authenticate itself with the proxy.

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 (408) indicating that the client did not produce a request within the time that the server was prepared to wait.

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 (416) indicating that the server cannot serve the requested byte range.

Status code (205) indicating that the agent SHOULD reset the document view which caused the request to be sent.

Status code (303) indicating that the response to the request can be found under a different URI.

Status code (503) indicating that the HTTP server is temporarily overloaded, and unable to handle the request.

Status code (101) indicating the server is switching protocols according to Upgrade header.

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 (401) indicating that the request requires HTTP authentication.

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 (305) indicating that the requested resource MUST be accessed through the proxy given by the Location field.

Adds the specified cookie to the response. This method can be called multiple times to set more than one cookie.

Parameters

cookie:Cookie

the Cookie to return to the client

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.

Parameters

name:String

the name of the header to set

date:long

the additional date value

See Also

setDateHeader

Adds a response header with the given name and value. This method allows response headers to have multiple values.

Parameters

name:String

the name of the header

value:String

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 integer value. This method allows response headers to have multiple values.

Parameters

name:String

the name of the header

value:int

the assigned integer value

See Also

setIntHeader

Returns a boolean indicating whether the named response header has already been set.

Parameters

name:String

the header name

Returns:boolean

true if the named response header has already been set; false otherwise

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. 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.

Parameters

url:String

the url to be encoded.

Returns:String

the encoded URL if encoding is needed; the unchanged URL otherwise.

See Also

sendRedirect

Encodes the specified URL by including the session ID in it, 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.

Parameters

url:String

the url to be encoded.

Returns:String

the encoded URL if encoding is needed; the unchanged URL otherwise.

Return the value for the specified header, or null if this header has not been set. If more than one value was added for this name, only the first is returned; use getHeaders(String) to retrieve all of them.

Parameters

name:String

Header name to look up

Returns:String

The first value for the specified header. This is the raw value so if multiple values are specified in the first header then they will be returned as a single header value .

Since

Servlet 3.0

Get the header names set for this HTTP response.

Returns:Collection<String>

The header names set for this HTTP response.

Since

Servlet 3.0

Return a Collection of all the header values associated with the specified header name.

Parameters

name:String

Header name to look up

Returns:Collection<String>

The values for the specified header. These are the raw values so if multiple values are specified in a single header that will be returned as a single header value.

Since

Servlet 3.0

Get the HTTP status code for this Response.

Returns:int

The HTTP status code for this Response

Since

Servlet 3.0

Obtain the supplier of the trailer headers.
The default implementation returns null.

Returns:Supplier<Map<String, String>>

The supplier for the trailer headers

Since

Servlet 4.0

Sends an error response to the client using the specified status code and clears the output 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", leaving cookies and other headers unmodified. 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.

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.

Parameters

sc:int

the error status code

msg:String

the descriptive message

Exceptions

IOException:

If an input or output exception occurs

IllegalStateException:

If the response was committed

Sends an error response to the client using the specified status code and clears the buffer. This is equivalent to calling sendError(int, String) with the same status code and null for the message.

Parameters

sc:int

the error status code

Exceptions

IOException:

If an input or output exception occurs

IllegalStateException:

If the response was committed before this method call

Sends a redirect response to the client using the specified redirect location URL with the status code SC_FOUND 302 (Found), clears the response buffer and commits the response. The response buffer will be replaced with a short hypertext note as per RFC 9110.

This method has no effect if called from an include.

This method accepts both relative and absolute URLs. Absolute URLs passed to this method are used as provided as the redirect location URL. Relative URLs are converted to absolute URLs. If converting a relative URL to an absolute URL then:

• 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.

Parameters

location:String

the redirect location URL (may be absolute or relative)

Exceptions

IOException:

If an input or output exception occurs

IllegalArgumentException:

If a relative URL is given and cannot be converted into an absolute URL

IllegalStateException:

If the response was already committed when this method was called

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.

Parameters

name:String

the name of the header to set

date:long

the assigned date value

See Also

containsHeader, addDateHeader

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.

Parameters

name:String

the name of the header

value:String

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 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.

Parameters

name:String

the name of the header

value:int

the assigned integer value

See Also

containsHeader, addIntHeader

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 status codes SC_OK or SC_MOVED_TEMPORARILY). If there is an error, and the caller wishes to invoke an error-page defined in the web application, the sendError method should be used instead.

The container clears the buffer and sets the Location header, preserving cookies and other headers.

Parameters

sc:int

the status code

See Also

sendError

Configure the supplier of the trailer headers. The supplier will be called in the scope of the thread that completes the response.
Trailers that don't meet the requirements of RFC 7230, section 4.1.2 will be ignored.
The default implementation is a NO-OP.

Parameters

supplier:Supplier<Map<String, String>>

The supplier for the trailer headers

Exceptions

IllegalStateException:

if this method is called when the underlying protocol does not support trailer headers or if using HTTP/1.1 and the response has already been committed

Since

Servlet 4.0