Package org.apache.catalina.connector

Class ResponseFacade

java.lang.Object

org.apache.catalina.connector.ResponseFacade

All Implemented Interfaces:

HttpServletResponse, ServletResponse

public class ResponseFacade
extends Object
implements HttpServletResponse

Facade class that wraps a Coyote response object. All methods are delegated to the wrapped response.

Author:

Remy Maucherat

Field Summary

Fields

Modifier and Type	Field	Description
protected Response	response	The wrapped response.
protected static final StringManager	sm	The string manager for this package.

Fields inherited from interface jakarta.servlet.http.HttpServletResponse

SC_ACCEPTED, SC_BAD_GATEWAY, SC_BAD_REQUEST, SC_CONFLICT, SC_CONTINUE, SC_CREATED, SC_EXPECTATION_FAILED, SC_FORBIDDEN, SC_FOUND, SC_GATEWAY_TIMEOUT, SC_GONE, SC_HTTP_VERSION_NOT_SUPPORTED, SC_INTERNAL_SERVER_ERROR, SC_LENGTH_REQUIRED, SC_METHOD_NOT_ALLOWED, SC_MOVED_PERMANENTLY, SC_MOVED_TEMPORARILY, SC_MULTIPLE_CHOICES, SC_NO_CONTENT, SC_NON_AUTHORITATIVE_INFORMATION, SC_NOT_ACCEPTABLE, SC_NOT_FOUND, SC_NOT_IMPLEMENTED, SC_NOT_MODIFIED, SC_OK, SC_PARTIAL_CONTENT, SC_PAYMENT_REQUIRED, SC_PRECONDITION_FAILED, SC_PROXY_AUTHENTICATION_REQUIRED, SC_REQUEST_ENTITY_TOO_LARGE, SC_REQUEST_TIMEOUT, SC_REQUEST_URI_TOO_LONG, SC_REQUESTED_RANGE_NOT_SATISFIABLE, SC_RESET_CONTENT, SC_SEE_OTHER, SC_SERVICE_UNAVAILABLE, SC_SWITCHING_PROTOCOLS, SC_TEMPORARY_REDIRECT, SC_UNAUTHORIZED, SC_UNSUPPORTED_MEDIA_TYPE, SC_USE_PROXY

Constructor Summary

Constructors

Constructor	Description
ResponseFacade(Response response)	Construct a wrapper for the specified response.

Method Summary

Modifier and Type	Method	Description
void	addCookie(Cookie cookie)	Adds the specified cookie to the response.
void	addDateHeader(String name, long date)	Adds a response header with the given name and date-value.
void	addHeader(String name, String value)	Adds a response header with the given name and value.
void	addIntHeader(String name, int value)	Adds a response header with the given name and integer value.
void	clear()	Clear facade.
protected Object	clone()	Prevent cloning the facade.
boolean	containsHeader(String name)	Returns a boolean indicating whether the named response header has already been set.
String	encodeRedirectURL(String url)	Encodes the specified URL for use in the sendRedirect method or, if encoding is not needed, returns the URL unchanged.
String	encodeURL(String url)	Encodes the specified URL by including the session ID in it, or, if encoding is not needed, returns the URL unchanged.
void	finish()
void	flushBuffer()	Forces any content in the buffer to be written to the client.
int	getBufferSize()	Returns the actual buffer size used for the response.
String	getCharacterEncoding()	Returns the name of the character encoding (MIME charset) used for the body sent in this response.
String	getContentType()	Returns the content type used for the MIME body sent in this response.
long	getContentWritten()
String	getHeader(String name)	Return the value for the specified header, or null if this header has not been set.
Collection<String>	getHeaderNames()	Get the header names set for this HTTP response.
Collection<String>	getHeaders(String name)	Return a Collection of all the header values associated with the specified header name.
Locale	getLocale()	Returns the locale specified for this response using the ServletResponse.setLocale(java.util.Locale) method.
ServletOutputStream	getOutputStream()	Returns a ServletOutputStream suitable for writing binary data in the response.
int	getStatus()	Get the HTTP status code for this Response.
Supplier<Map<String,String>>	getTrailerFields()	Obtain the supplier of the trailer headers.
PrintWriter	getWriter()	Returns a PrintWriter object that can send character text to the client.
boolean	isCommitted()	Returns a boolean indicating if the response has been committed.
boolean	isFinished()
void	reset()	Clears any data that exists in the buffer as well as the status code and headers.
void	resetBuffer()	Clears the content of the underlying buffer in the response without clearing headers or status code.
void	sendEarlyHints()
void	sendError(int sc)	Sends an error response to the client using the specified status code and clears the buffer.
void	sendError(int sc, String msg)	Sends an error response to the client using the specified status code and clears the output buffer.
void	sendRedirect(String location)	Sends a redirect response to the client using the specified redirect location URL with the status code HttpServletResponse.SC_FOUND 302 (Found), clears the response buffer and commits the response.
void	setBufferSize(int size)	Sets the preferred buffer size for the body of the response.
void	setCharacterEncoding(String encoding)	Sets the character encoding (MIME charset) of the response being sent to the client, for example, to UTF-8.
void	setContentLength(int len)	Sets the length of the content body in the response In HTTP servlets, this method sets the HTTP Content-Length header.
void	setContentLengthLong(long length)	Sets the length of the content body in the response In HTTP servlets, this method sets the HTTP Content-Length header.
void	setContentType(String type)	Sets the content type of the response being sent to the client, if the response has not been committed yet.
void	setDateHeader(String name, long date)	Sets a response header with the given name and date-value.
void	setHeader(String name, String value)	Sets a response header with the given name and value.
void	setIntHeader(String name, int value)	Sets a response header with the given name and integer value.
void	setLocale(Locale loc)	Sets the locale of the response, if the response has not been committed yet.
void	setStatus(int sc)	Sets the status code for this response.
void	setTrailerFields(Supplier<Map<String,String>> supplier)	Configure the supplier of the trailer headers.

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

sm

protected static final StringManager sm

The string manager for this package.

response

protected Response response

The wrapped response.

Constructor Details

ResponseFacade

public ResponseFacade(Response response)

Construct a wrapper for the specified response.

Parameters:

response - The response to be wrapped

Method Details

clear

public void clear()

Clear facade.

clone

protected Object clone()
                throws CloneNotSupportedException

Prevent cloning the facade.

Overrides:

clone in class Object

Throws:

CloneNotSupportedException

finish

public void finish()

isFinished

public boolean isFinished()

getContentWritten

public long getContentWritten()

getCharacterEncoding

public String getCharacterEncoding()

Description copied from interface: jakarta.servlet.ServletResponse

Returns the name of the character encoding (MIME charset) used for the body sent in this response. The charset for the MIME body response can be specified explicitly or implicitly. The priority order for specifying the response body is:

1. explicitly per request using ServletResponse.setCharacterEncoding(java.lang.String) and ServletResponse.setContentType(java.lang.String)
2. implicitly per request using ServletResponse.setLocale(java.util.Locale)
3. per web application via the deployment descriptor or ServletContext.setRequestCharacterEncoding(String)
4. container default via vendor specific configuration
5. ISO-8859-1

Calls made to ServletResponse.setCharacterEncoding(java.lang.String), ServletResponse.setContentType(java.lang.String) or ServletResponse.setLocale(java.util.Locale) after getWriter has been called or after the response has been committed have no effect on the character encoding. If no character encoding has been specified, ISO-8859-1 is returned.

See RFC 2047 (http://www.ietf.org/rfc/rfc2047.txt) for more information about character encoding and MIME.

Specified by:

getCharacterEncoding in interface ServletResponse

Returns:

a String specifying the name of the character encoding, for example, UTF-8

getOutputStream

public ServletOutputStream getOutputStream()
                                    throws IOException

Description copied from interface: jakarta.servlet.ServletResponse

Returns a ServletOutputStream suitable for writing binary data in the response. The servlet container does not encode the binary data.

Calling flush() on the ServletOutputStream commits the response. Either this method or ServletResponse.getWriter() may be called to write the body, not both.

Specified by:

getOutputStream in interface ServletResponse

Returns:

a ServletOutputStream for writing binary data

Throws:

IOException - if an input or output exception occurred

See Also:

• ServletResponse.getWriter()

getWriter

public PrintWriter getWriter()
                      throws IOException

Description copied from interface: jakarta.servlet.ServletResponse

Returns a PrintWriter object that can send character text to the client. The PrintWriter uses the character encoding returned by ServletResponse.getCharacterEncoding(). If the response's character encoding has not been specified as described in getCharacterEncoding (i.e., the method just returns the default value ISO-8859-1), getWriter updates it to ISO-8859-1.

Calling flush() on the PrintWriter commits the response.

Either this method or ServletResponse.getOutputStream() may be called to write the body, not both.

Specified by:

getWriter in interface ServletResponse

Returns:

a PrintWriter object that can return character data to the client

Throws:

IOException - if an input or output exception occurred

See Also:

• ServletResponse.getOutputStream()
• ServletResponse.setCharacterEncoding(java.lang.String)

setContentLength

public void setContentLength(int len)

Description copied from interface: jakarta.servlet.ServletResponse

Sets the length of the content body in the response In HTTP servlets, this method sets the HTTP Content-Length header.

Specified by:

setContentLength in interface ServletResponse

Parameters:

len - an integer specifying the length of the content being returned to the client; sets the Content-Length header

setContentLengthLong

public void setContentLengthLong(long length)

Description copied from interface: jakarta.servlet.ServletResponse

Sets the length of the content body in the response In HTTP servlets, this method sets the HTTP Content-Length header.

Specified by:

setContentLengthLong in interface ServletResponse

Parameters:

length - an integer specifying the length of the content being returned to the client; sets the Content-Length header

setContentType

public void setContentType(String type)

Description copied from interface: jakarta.servlet.ServletResponse

Sets the content type of the response being sent to the client, if the response has not been committed yet. The given content type may include a character encoding specification, for example, text/html;charset=UTF-8. The response's character encoding is only set from the given content type if this method is called before getWriter is called.

This method may be called repeatedly to change content type and character encoding. This method has no effect if called after the response has been committed. It does not set the response's character encoding if it is called after getWriter has been called or after the response has been committed.

Containers must communicate the content type and the character encoding used for the servlet response's writer to the client if the protocol provides a way for doing so. In the case of HTTP, the Content-Type header is used.

Specified by:

setContentType in interface ServletResponse

Parameters:

type - a String specifying the MIME type of the content

See Also:

• ServletResponse.setLocale(java.util.Locale)
• ServletResponse.setCharacterEncoding(java.lang.String)
• ServletResponse.getOutputStream()
• ServletResponse.getWriter()

setBufferSize

public void setBufferSize(int size)

Description copied from interface: jakarta.servlet.ServletResponse

Sets the preferred buffer size for the body of the response. The servlet container will use a buffer at least as large as the size requested. The actual buffer size used can be found using getBufferSize.

A larger buffer allows more content to be written before anything is actually sent, thus providing the servlet with more time to set appropriate status codes and headers. A smaller buffer decreases server memory load and allows the client to start receiving data more quickly.

This method must be called before any response body content is written; if content has been written or the response object has been committed, this method throws an IllegalStateException.

Specified by:

setBufferSize in interface ServletResponse

Parameters:

size - the preferred buffer size

See Also:

• ServletResponse.getBufferSize()
• ServletResponse.flushBuffer()
• ServletResponse.isCommitted()
• ServletResponse.reset()

getBufferSize

public int getBufferSize()

Description copied from interface: jakarta.servlet.ServletResponse

Returns the actual buffer size used for the response. If no buffering is used, this method returns 0.

Specified by:

getBufferSize in interface ServletResponse

Returns:

the actual buffer size used

See Also:

• ServletResponse.setBufferSize(int)
• ServletResponse.flushBuffer()
• ServletResponse.isCommitted()
• ServletResponse.reset()

flushBuffer

public void flushBuffer()
                 throws IOException

Description copied from interface: jakarta.servlet.ServletResponse

Forces any content in the buffer to be written to the client. A call to this method automatically commits the response, meaning the status code and headers will be written.

Specified by:

flushBuffer in interface ServletResponse

Throws:

IOException - if an I/O occurs during the flushing of the response

See Also:

• ServletResponse.setBufferSize(int)
• ServletResponse.getBufferSize()
• ServletResponse.isCommitted()
• ServletResponse.reset()

resetBuffer

public void resetBuffer()

Description copied from interface: jakarta.servlet.ServletResponse

Clears the content of the underlying buffer in the response without clearing headers or status code. If the response has been committed, this method throws an IllegalStateException.

Specified by:

resetBuffer in interface ServletResponse

See Also:

• ServletResponse.setBufferSize(int)
• ServletResponse.getBufferSize()
• ServletResponse.isCommitted()
• ServletResponse.reset()

isCommitted

public boolean isCommitted()

Description copied from interface: jakarta.servlet.ServletResponse

Returns a boolean indicating if the response has been committed. A committed response has already had its status code and headers written.

Specified by:

isCommitted in interface ServletResponse

Returns:

a boolean indicating if the response has been committed

See Also:

• ServletResponse.setBufferSize(int)
• ServletResponse.getBufferSize()
• ServletResponse.flushBuffer()
• ServletResponse.reset()

reset

public void reset()

Description copied from interface: jakarta.servlet.ServletResponse

Clears any data that exists in the buffer as well as the status code and headers. If the response has been committed, this method throws an IllegalStateException.

Specified by:

reset in interface ServletResponse

See Also:

• ServletResponse.setBufferSize(int)
• ServletResponse.getBufferSize()
• ServletResponse.flushBuffer()
• ServletResponse.isCommitted()

setLocale

public void setLocale(Locale loc)

Description copied from interface: jakarta.servlet.ServletResponse

Sets the locale of the response, if the response has not been committed yet. It also sets the response's character encoding appropriately for the locale, if the character encoding has not been explicitly set using ServletResponse.setContentType(java.lang.String) or ServletResponse.setCharacterEncoding(java.lang.String), getWriter hasn't been called yet, and the response hasn't been committed yet. If the deployment descriptor contains a locale-encoding-mapping-list element, and that element provides a mapping for the given locale, that mapping is used. Otherwise, the mapping from locale to character encoding is container dependent.

This method may be called repeatedly to change locale and character encoding. The method has no effect if called after the response has been committed. It does not set the response's character encoding if it is called after ServletResponse.setContentType(java.lang.String) has been called with a charset specification, after ServletResponse.setCharacterEncoding(java.lang.String) has been called, after getWriter has been called, or after the response has been committed.

Containers must communicate the locale and the character encoding used for the servlet response's writer to the client if the protocol provides a way for doing so. In the case of HTTP, the locale is communicated via the Content-Language header, the character encoding as part of the Content-Type header for text media types. Note that the character encoding cannot be communicated via HTTP headers if the servlet does not specify a content type; however, it is still used to encode text written via the servlet response's writer.

Specified by:

setLocale in interface ServletResponse

Parameters:

loc - the locale of the response

See Also:

• ServletResponse.getLocale()
• ServletResponse.setContentType(java.lang.String)
• ServletResponse.setCharacterEncoding(java.lang.String)

getLocale

public Locale getLocale()

Description copied from interface: jakarta.servlet.ServletResponse

Returns the locale specified for this response using the ServletResponse.setLocale(java.util.Locale) method. Calls made to setLocale after the response is committed have no effect.

Specified by:

getLocale in interface ServletResponse

Returns:

The locale specified for this response using the ServletResponse.setLocale(java.util.Locale) method. If no locale has been specified, the container's default locale is returned.

See Also:

• ServletResponse.setLocale(java.util.Locale)

addCookie

public void addCookie(Cookie cookie)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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

Specified by:

addCookie in interface HttpServletResponse

Parameters:

cookie - the Cookie to return to the client

containsHeader

public boolean containsHeader(String name)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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

Specified by:

containsHeader in interface HttpServletResponse

Parameters:

name - the header name

Returns:

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

encodeURL

public String encodeURL(String url)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

encodeURL in interface HttpServletResponse

Parameters:

url - the url to be encoded.

Returns:

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

encodeRedirectURL

public String encodeRedirectURL(String url)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

encodeRedirectURL in interface HttpServletResponse

Parameters:

url - the url to be encoded.

Returns:

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

See Also:

• HttpServletResponse.sendRedirect(java.lang.String)

sendEarlyHints

public void sendEarlyHints()

sendError

public void sendError(int sc,
 String msg)
               throws IOException

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.

Calling sendError with a status code of 103 differs from the usual behavior. Sending 103 will trigger the container to send a "103 Early Hints" informational response including all current headers. The application can continue to use the request and response after calling sendError with a 103 status code, including triggering a more typical response of any type.

Starting with Tomcat 12, applications should use sendEarlyHints().

Specified by:

sendError in interface HttpServletResponse

Parameters:

sc - the error status code

msg - the descriptive message

Throws:

IOException - If an input or output exception occurs

sendError

public void sendError(int sc)
               throws IOException

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

Calling sendError with a status code of 103 differs from the usual behavior. Sending 103 will trigger the container to send a "103 Early Hints" informational response including all current headers. The application can continue to use the request and response after calling sendError with a 103 status code, including triggering a more typical response of any type.

Starting with Tomcat 12, applications should use sendEarlyHints().

Specified by:

sendError in interface HttpServletResponse

Parameters:

sc - the error status code

Throws:

IOException - If an input or output exception occurs

sendRedirect

public void sendRedirect(String location)
                  throws IOException

Description copied from interface: jakarta.servlet.http.HttpServletResponse

Sends a redirect response to the client using the specified redirect location URL with the status code HttpServletResponse.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.

Specified by:

sendRedirect in interface HttpServletResponse

Parameters:

location - the redirect location URL (may be absolute or relative)

Throws:

IOException - If an input or output exception occurs

setDateHeader

public void setDateHeader(String name,
 long date)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

setDateHeader in interface HttpServletResponse

Parameters:

name - the name of the header to set

date - the assigned date value

See Also:

• HttpServletResponse.containsHeader(java.lang.String)
• HttpServletResponse.addDateHeader(java.lang.String, long)

addDateHeader

public void addDateHeader(String name,
 long date)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

addDateHeader in interface HttpServletResponse

Parameters:

name - the name of the header to set

date - the additional date value

See Also:

• HttpServletResponse.setDateHeader(java.lang.String, long)

setHeader

public void setHeader(String name,
 String value)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

setHeader in interface HttpServletResponse

Parameters:

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:

• HttpServletResponse.containsHeader(java.lang.String)
• HttpServletResponse.addHeader(java.lang.String, java.lang.String)

addHeader

public void addHeader(String name,
 String value)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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

Specified by:

addHeader in interface HttpServletResponse

Parameters:

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:

• HttpServletResponse.setHeader(java.lang.String, java.lang.String)

setIntHeader

public void setIntHeader(String name,
 int value)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

setIntHeader in interface HttpServletResponse

Parameters:

name - the name of the header

value - the assigned integer value

See Also:

• HttpServletResponse.containsHeader(java.lang.String)
• HttpServletResponse.addIntHeader(java.lang.String, int)

addIntHeader

public void addIntHeader(String name,
 int value)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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

Specified by:

addIntHeader in interface HttpServletResponse

Parameters:

name - the name of the header

value - the assigned integer value

See Also:

• HttpServletResponse.setIntHeader(java.lang.String, int)

setStatus

public void setStatus(int sc)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

setStatus in interface HttpServletResponse

Parameters:

sc - the status code

See Also:

• HttpServletResponse.sendError(int, java.lang.String)

getContentType

public String getContentType()

Description copied from interface: jakarta.servlet.ServletResponse

Returns the content type used for the MIME body sent in this response. The content type proper must have been specified using ServletResponse.setContentType(java.lang.String) before the response is committed. If no content type has been specified, this method returns null. If a content type has been specified and a character encoding has been explicitly or implicitly specified as described in ServletResponse.getCharacterEncoding(), the charset parameter is included in the string returned. If no character encoding has been specified, the charset parameter is omitted.

Specified by:

getContentType in interface ServletResponse

Returns:

a String specifying the content type, for example, text/html; charset=UTF-8, or null

setCharacterEncoding

public void setCharacterEncoding(String encoding)

Description copied from interface: jakarta.servlet.ServletResponse

Sets the character encoding (MIME charset) of the response being sent to the client, for example, to UTF-8. If the character encoding has already been set by container default, ServletContext default, ServletResponse.setContentType(java.lang.String) or ServletResponse.setLocale(java.util.Locale), this method overrides it. Calling ServletResponse.setContentType(java.lang.String) with the String of text/html and calling this method with the String of UTF-8 is equivalent with calling setContentType with the String of text/html; charset=UTF-8.

This method can be called repeatedly to change the character encoding. This method has no effect if it is called after getWriter has been called or after the response has been committed.

Containers must communicate the character encoding used for the servlet response's writer to the client if the protocol provides a way for doing so. In the case of HTTP, the character encoding is communicated as part of the Content-Type header for text media types. Note that the character encoding cannot be communicated via HTTP headers if the servlet does not specify a content type; however, it is still used to encode text written via the servlet response's writer.

Specified by:

setCharacterEncoding in interface ServletResponse

Parameters:

encoding - a String specifying only the character set defined by IANA Character Sets (http://www.iana.org/assignments/character-sets)

See Also:

• #setLocale

getStatus

public int getStatus()

Description copied from interface: jakarta.servlet.http.HttpServletResponse

Get the HTTP status code for this Response.

Specified by:

getStatus in interface HttpServletResponse

Returns:

The HTTP status code for this Response

getHeader

public String getHeader(String name)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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 HttpServletResponse.getHeaders(String) to retrieve all of them.

Specified by:

getHeader in interface HttpServletResponse

Parameters:

name - Header name to look up

Returns:

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 .

getHeaderNames

public Collection<String> getHeaderNames()

Description copied from interface: jakarta.servlet.http.HttpServletResponse

Get the header names set for this HTTP response.

Specified by:

getHeaderNames in interface HttpServletResponse

Returns:

The header names set for this HTTP response.

getHeaders

public Collection<String> getHeaders(String name)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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

Specified by:

getHeaders in interface HttpServletResponse

Parameters:

name - Header name to look up

Returns:

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.

setTrailerFields

public void setTrailerFields(Supplier<Map<String,String>> supplier)

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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.

Specified by:

setTrailerFields in interface HttpServletResponse

Parameters:

supplier - The supplier for the trailer headers

getTrailerFields

public Supplier<Map<String,String>> getTrailerFields()

Description copied from interface: jakarta.servlet.http.HttpServletResponse

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

Specified by:

getTrailerFields in interface HttpServletResponse

Returns:

The supplier for the trailer headers