| |
|
| javax.servlet.ServletResponse
All known Subclasses: javax.servlet.ServletResponseWrapper,
| ServletResponse | | public interface ServletResponse (Code) | | Defines an object to assist a servlet in sending a response to the client.
The servlet container creates a ServletResponse object and
passes it as an argument to the servlet's service method.
To send binary data in a MIME body response, use
the
ServletOutputStream returned by
ServletResponse.getOutputStream .
To send character data, use the PrintWriter object
returned by
ServletResponse.getWriter . To mix binary and text data,
for example, to create a multipart response, use a
ServletOutputStream and manage the character sections
manually.
The charset for the MIME body response can be specified
explicitly using the
ServletResponse.setCharacterEncoding and
ServletResponse.setContentType methods, or implicitly
using the
ServletResponse.setLocale method.
Explicit specifications take precedence over
implicit specifications. If no charset is specified, ISO-8859-1 will be
used. The setCharacterEncoding,
setContentType, or setLocale method must
be called before getWriter and before committing
the response for the character encoding to be used.
See the Internet RFCs such as
RFC 2045 for more information on MIME. Protocols such as SMTP
and HTTP define profiles of MIME, and those standards
are still evolving.
author:
Various
version:
$Version$
See Also: ServletOutputStream |
| Method Summary | |
| public void | flushBuffer()
Forces any content in the buffer to be written to the client. | | public int | getBufferSize()
Returns the actual buffer size used for the response. | | public String | getCharacterEncoding()
Returns the name of the character encoding (MIME charset)
used for the body sent in this response.
The character encoding may have been specified explicitly
using the
ServletResponse.setCharacterEncoding or
ServletResponse.setContentType methods, or implicitly using the
ServletResponse.setLocale method. | | public String | getContentType()
Returns the content type used for the MIME body
sent in this response. | | public Locale | getLocale()
Returns the locale specified for this response
using the
ServletResponse.setLocale method. | | public ServletOutputStream | getOutputStream()
Returns a
ServletOutputStream suitable for writing binary
data in the response. | | public PrintWriter | getWriter()
Returns a PrintWriter object that
can send character text to the client. | | public boolean | isCommitted()
Returns a boolean indicating if the response has been
committed. | | public void | reset()
Clears any data that exists in the buffer as well as the status code and
headers. | | public void | resetBuffer()
Clears the content of the underlying buffer in the response without
clearing headers or status code. | | public void | setBufferSize(int size)
Sets the preferred buffer size for the body of the response. | | public void | setCharacterEncoding(String charset)
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
ServletResponse.setContentType or
ServletResponse.setLocale ,
this method overrides it.
Calling
ServletResponse.setContentType 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. | | public 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. | | public void | setContentType(String type)
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. | | public void | setLocale(Locale loc)
Sets the locale of the response, if the response has not been
committed yet. |
| getCharacterEncoding | | public String getCharacterEncoding()(Code) | | Returns the name of the character encoding (MIME charset)
used for the body sent in this response.
The character encoding may have been specified explicitly
using the
ServletResponse.setCharacterEncoding or
ServletResponse.setContentType methods, or implicitly using the
ServletResponse.setLocale method. Explicit specifications take
precedence over implicit specifications. Calls made
to these methods 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.
a String specifying thename of the character encoding, forexample, UTF-8 |
| getContentType | | public String getContentType()(Code) | | Returns the content type used for the MIME body
sent in this response. The content type proper must
have been specified using
ServletResponse.setContentType 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.
a String specifying thecontent type, for example,text/html; charset=UTF-8,or null
since:
2.4 |
| getLocale | | public Locale getLocale()(Code) | | Returns the locale specified for this response
using the
ServletResponse.setLocale method. Calls made to
setLocale after the response is committed
have no effect. If no locale has been specified,
the container's default locale is returned.
See Also: ServletResponse.setLocale |
| getWriter | | public PrintWriter getWriter() throws IOException(Code) | | 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.
a PrintWriter object that can return character data to the client
exception:
UnsupportedEncodingException - if the character encoding returnedby getCharacterEncoding cannot be used
exception:
IllegalStateException - if the getOutputStreammethod has already been called for this response object
exception:
IOException - if an input or output exception occurred
See Also: ServletResponse.getOutputStream
See Also: ServletResponse.setCharacterEncoding |
| setBufferSize | | public void setBufferSize(int size)(Code) | | 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.
Parameters:
size - the preferred buffer size
exception:
IllegalStateException - if this method is called aftercontent has been written
See Also: ServletResponse.getBufferSize
See Also: ServletResponse.flushBuffer
See Also: ServletResponse.isCommitted
See Also: ServletResponse.reset |
| setCharacterEncoding | | public void setCharacterEncoding(String charset)(Code) | | 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
ServletResponse.setContentType or
ServletResponse.setLocale ,
this method overrides it.
Calling
ServletResponse.setContentType 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.
Parameters:
charset - a String specifying only the character setdefined by IANA Character Sets(http://www.iana.org/assignments/character-sets)
See Also: ServletResponse.setContentType
See Also: #setLocale
since:
2.4 |
| setContentLength | | public void setContentLength(int len)(Code) | | Sets the length of the content body in the response
In HTTP servlets, this method sets the HTTP Content-Length header.
Parameters:
len - an integer specifying the length of the content being returned to the client; setsthe Content-Length header |
| setContentType | | public void setContentType(String type)(Code) | | 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.
Parameters:
type - a String specifying the MIME type of the content
See Also: ServletResponse.setLocale
See Also: ServletResponse.setCharacterEncoding
See Also: ServletResponse.getOutputStream
See Also: ServletResponse.getWriter |
| setLocale | | public void setLocale(Locale loc)(Code) | | 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 or
ServletResponse.setCharacterEncoding , 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 has been called with a charset specification, after
ServletResponse.setCharacterEncoding 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.
Parameters:
loc - the locale of the response
See Also: ServletResponse.getLocale
See Also: ServletResponse.setContentType
See Also: ServletResponse.setCharacterEncoding |
|
|
|