public interface Response extends ResponseHeader
OutputStream
can be acquired via this interface
which can be used to write the response body. A buffer size can be
specified when acquiring the output stream which allows data to
be buffered until it over flows or is flushed explicitly. This
buffering allows a partially written response body to be reset.
This should never allow the message body be sent if it should not be sent with the headers as of RFC 2616 rules for the presence of a message body. A message body must not be included with a HEAD request or with a 304 or a 204 response. A proper implementation of this will prevent a message body being sent if the response is to a HEAD request of if there is a 304 or 204 response code.
It is important to note that the Response
controls
the processing of the HTTP pipeline. The next HTTP request is
not processed until the response has been sent. To ensure that
the response is sent the close
method of the response
or the output stream should be used. This will notify the server
to dispatch the next request in the pipeline for processing.
Modifier and Type | Method and Description |
---|---|
void |
close()
This is used to close the connection and commit the request.
|
void |
commit()
This is used to write the headers that where given to the
Response . |
WritableByteChannel |
getByteChannel()
Used to write a message body with the
Response . |
WritableByteChannel |
getByteChannel(int size)
Used to write a message body with the
Response . |
OutputStream |
getOutputStream()
Used to write a message body with the
Response . |
OutputStream |
getOutputStream(int size)
Used to write a message body with the
Response . |
PrintStream |
getPrintStream()
This method is provided for convenience so that the HTTP content
can be written using the
print methods provided by
the PrintStream . |
PrintStream |
getPrintStream(int size)
This method is provided for convenience so that the HTTP content
can be written using the
print methods provided by
the PrintStream . |
long |
getResponseTime()
This represents the time at which the response has fully written.
|
boolean |
isCommitted()
This can be used to determine whether the
Response
has been committed. |
boolean |
isKeepAlive()
This is used to determine if the HTTP response message is a
keep alive message or if the underlying socket was closed.
|
void |
reset()
This can be used to determine whether the
Response
has been committed. |
void |
setContentLength(long length)
This should be used when the size of the message body is known.
|
void |
setContentType(String type)
This is used to set the content type for the response.
|
addDate, addInteger, addValue, getContentLength, getContentType, getCookie, getCookies, getDate, getHeader, getInteger, getNames, getTransferEncoding, getValue, getValue, getValues, setCookie, setCookie, setDate, setInteger, setLong, setValue, toString
getCode, getDescription, getMajor, getMinor, getStatus, setCode, setDescription, setMajor, setMinor, setStatus
void setContentLength(long length)
This removes any previous Content-Length headers from the message header. This will then set the appropriate Content-Length header with the correct length. If a the Connection header is set with the close token then the semantics of the connection are such that the server will close it once the output stream or request is closed.
length
- this is the length of the HTTP message bodyvoid setContentType(String type)
type
- this is the type that is to be set in the responseOutputStream getOutputStream() throws IOException
Response
. The
semantics of this OutputStream
will be determined
by the HTTP version of the client, and whether or not the content
length has been set, through the setContentLength
method. If the length of the output is not known then the output
is chunked for HTTP/1.1 clients and closed for HTTP/1.0 clients.IOException
OutputStream getOutputStream(int size) throws IOException
Response
. The
semantics of this OutputStream
will be determined
by the HTTP version of the client, and whether or not the content
length has been set, through the setContentLength
method. If the length of the output is not known then the output
is chunked for HTTP/1.1 clients and closed for HTTP/1.0 clients.
This will ensure that there is buffering done so that the output
can be reset using the reset
method. This will
enable the specified number of bytes to be written without
committing the response. This specified size is the minimum size
that the response buffer must be.
IOException
PrintStream getPrintStream() throws IOException
print
methods provided by
the PrintStream
. This will basically wrap the
getOutputStream
with a buffer size of zero.
The retrieved PrintStream
uses the charset used to
describe the content, with the Content-Type header. This will
check the charset parameter of the contents MIME type. So if
the Content-Type was text/plain; charset=UTF-8
the
resulting PrintStream
would encode the written data
using the UTF-8 encoding scheme. Care must be taken to ensure
that bytes written to the stream are correctly encoded.
Implementations of the Response
must guarantee
that this can be invoked repeatedly without effecting any issued
OutputStream
or PrintStream
object.
IOException
PrintStream getPrintStream(int size) throws IOException
print
methods provided by
the PrintStream
. This will basically wrap the
getOutputStream
with a specified buffer size.
The retrieved PrintStream
uses the charset used to
describe the content, with the Content-Type header. This will
check the charset parameter of the contents MIME type. So if
the Content-Type was text/plain; charset=UTF-8
the
resulting PrintStream
would encode the written data
using the UTF-8 encoding scheme. Care must be taken to ensure
that bytes written to the stream are correctly encoded.
Implementations of the Response
must guarantee
that this can be invoked repeatedly without effecting any issued
OutputStream
or PrintStream
object.
size
- the minimum size that the response buffer must beIOException
WritableByteChannel getByteChannel() throws IOException
Response
. The
semantics of this WritableByteChannel
are determined
by the HTTP version of the client, and whether or not the content
length has been set, through the setContentLength
method. If the length of the output is not known then the output
is chunked for HTTP/1.1 clients and closed for HTTP/1.0 clients.IOException
WritableByteChannel getByteChannel(int size) throws IOException
Response
. The
semantics of this WritableByteChannel
are determined
by the HTTP version of the client, and whether or not the content
length has been set, through the setContentLength
method. If the length of the output is not known then the output
is chunked for HTTP/1.1 clients and closed for HTTP/1.0 clients.
This will ensure that there is buffering done so that the output
can be reset using the reset
method. This will
enable the specified number of bytes to be written without
committing the response. This specified size is the minimum size
that the response buffer must be.
size
- the minimum size that the response buffer must beIOException
long getResponseTime()
boolean isKeepAlive()
Connection
HTTP header, it can also be
implicitly indicated by using version HTTP/1.0.boolean isCommitted()
Response
has been committed. This is true if the Response
was committed, either due to an explicit invocation of the
commit
method or due to the writing of content. If
the Response
has committed the reset
method will not work in resetting content already written.void commit() throws IOException
Response
. Any further attempts to give headers
to the Response
will be futile as only the headers
that were given at the time of the first commit will be used
in the message header.
This also performs some final checks on the headers submitted. This is done to determine the optimal performance of the output. If no specific Connection header has been specified this will set the connection so that HTTP/1.0 closes by default.
IOException
- thrown if there was a problem writingvoid reset() throws IOException
Response
has been committed. This is true if the Response
was committed, either due to an explicit invocation of the
commit
method or due to the writing of content. If
the Response
has committed the reset
method will not work in resetting content already written.IOException
- thrown if there is a problem resettingvoid close() throws IOException
IOException
- thrown if there is a problem writingCopyright © 2017. All rights reserved.