HttpServerResponse (Vert.x Core 3.2.0 API)

All Superinterfaces:

StreamBase, WriteStream<Buffer>
```
public interface HttpServerResponse
extends WriteStream<Buffer>
```
Represents a server-side HTTP response.
An instance of this is created and associated to every instance of HttpServerRequest that.
It allows the developer to control the HTTP response that is sent back to the client for a particular HTTP request.
It contains methods that allow HTTP headers and trailers to be set, and for a body to be written out to the response.
It also allows files to be streamed by the kernel directly from disk to the outgoing HTTP connection, bypassing user space altogether (where supported by the underlying operating system). This is a very efficient way of serving files from the server since buffers do not have to be read one by one from the file and written to the outgoing socket.
It implements WriteStream so it can be used with Pump to pump data with flow control.

Author:

Tim Fox

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`HttpServerResponse`	`bodyEndHandler(Handler<Void> handler)` Provide a handler that will be called just before the last part of the body is written to the wire and the response is ended.
`long`	`bytesWritten()`
`void`	`close()` Close the underlying TCP connection corresponding to the request.
`boolean`	`closed()`
`HttpServerResponse`	`closeHandler(Handler<Void> handler)` Set a close handler for the response.
`HttpServerResponse`	`drainHandler(Handler<Void> handler)` Set a drain handler on the stream.
`void`	`end()` Ends the response.
`void`	`end(Buffer chunk)` Same as `end()` but writes some data to the response body before ending.
`void`	`end(String chunk)` Same as `end(Buffer)` but writes a String in UTF-8 encoding before ending the response.
`void`	`end(String chunk, String enc)` Same as `end(Buffer)` but writes a String with the specified encoding before ending the response.
`boolean`	`ended()`
`HttpServerResponse`	`exceptionHandler(Handler<Throwable> handler)` Set an exception handler on the write stream.
`int`	`getStatusCode()`
`String`	`getStatusMessage()`
`MultiMap`	`headers()`
`HttpServerResponse`	`headersEndHandler(Handler<Void> handler)` Provide a handler that will be called just before the headers are written to the wire.
`boolean`	`headWritten()`
`boolean`	`isChunked()`
`HttpServerResponse`	`putHeader(CharSequence name, CharSequence value)` Like `putHeader(String, String)` but using CharSequence
`HttpServerResponse`	`putHeader(CharSequence name, Iterable<CharSequence> values)` Like `putHeader(String, Iterable)` but with CharSequence Iterable
`HttpServerResponse`	`putHeader(String name, Iterable<String> values)` Like `putHeader(String, String)` but providing multiple values via a String Iterable
`HttpServerResponse`	`putHeader(String name, String value)` Put an HTTP header
`HttpServerResponse`	`putTrailer(CharSequence name, CharSequence value)` Like `putTrailer(String, String)` but using CharSequence
`HttpServerResponse`	`putTrailer(CharSequence name, Iterable<CharSequence> value)` Like `putTrailer(String, Iterable)` but with CharSequence Iterable
`HttpServerResponse`	`putTrailer(String name, Iterable<String> values)` Like `putTrailer(String, String)` but providing multiple values via a String Iterable
`HttpServerResponse`	`putTrailer(String name, String value)` Put an HTTP trailer
`default HttpServerResponse`	`sendFile(String filename)` Same as `sendFile(String, long)` using offset @code{0} which means starting from the beginning of the file.
`default HttpServerResponse`	`sendFile(String filename, Handler<AsyncResult<Void>> resultHandler)` Like `sendFile(String)` but providing a handler which will be notified once the file has been completely written to the wire.
`default HttpServerResponse`	`sendFile(String filename, long offset)` Same as `sendFile(String, long, long)` using length @code{Long.MAX_VALUE} which means until the end of the file.
`default HttpServerResponse`	`sendFile(String filename, long offset, Handler<AsyncResult<Void>> resultHandler)` Like `sendFile(String, long)` but providing a handler which will be notified once the file has been completely written to the wire.
`HttpServerResponse`	`sendFile(String filename, long offset, long length)` Ask the OS to stream a file as specified by `filename` directly from disk to the outgoing connection, bypassing userspace altogether (where supported by the underlying operating system.
`HttpServerResponse`	`sendFile(String filename, long offset, long length, Handler<AsyncResult<Void>> resultHandler)` Like `sendFile(String, long, long)` but providing a handler which will be notified once the file has been completely written to the wire.
`HttpServerResponse`	`setChunked(boolean chunked)` If `chunked` is `true`, this response will use HTTP chunked encoding, and each call to write to the body will correspond to a new HTTP chunk sent on the wire.
`HttpServerResponse`	`setStatusCode(int statusCode)` Set the status code.
`HttpServerResponse`	`setStatusMessage(String statusMessage)` Set the status message
`HttpServerResponse`	`setWriteQueueMaxSize(int maxSize)` Set the maximum size of the write queue to `maxSize`.
`MultiMap`	`trailers()`
`HttpServerResponse`	`write(Buffer data)` Write some data to the stream.
`HttpServerResponse`	`write(String chunk)` Write a `String` to the response body, encoded in UTF-8.
`HttpServerResponse`	`write(String chunk, String enc)` Write a `String` to the response body, encoded using the encoding `enc`.
`HttpServerResponse`	`writeContinue()` Used to write an interim 100 Continue response to signify that the client should send the rest of the request.

Methods inherited from interface io.vertx.core.streams.WriteStream
writeQueueFull

- Method Detail
  - exceptionHandler
```
HttpServerResponse exceptionHandler(Handler<Throwable> handler)
```
    Description copied from interface: WriteStream
    
    Set an exception handler on the write stream.
    
    Specified by:
    
    exceptionHandler in interface StreamBase
    
    Specified by:
    
    exceptionHandler in interface WriteStream<Buffer>
    
    Parameters:
    
    handler - the exception handler
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - write
```
HttpServerResponse write(Buffer data)
```
    Description copied from interface: WriteStream
    
    Write some data to the stream. The data is put on an internal write queue, and the write actually happens asynchronously. To avoid running out of memory by putting too much on the write queue, check the WriteStream.writeQueueFull() method before writing. This is done automatically if using a Pump.
    
    Specified by:
    
    write in interface WriteStream<Buffer>
    
    Parameters:
    
    data - the data to write
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - setWriteQueueMaxSize
```
HttpServerResponse setWriteQueueMaxSize(int maxSize)
```
    Description copied from interface: WriteStream
    
    Set the maximum size of the write queue to maxSize. You will still be able to write to the stream even if there is more than maxSize bytes in the write queue. This is used as an indicator by classes such as Pump to provide flow control.
    
    Specified by:
    
    setWriteQueueMaxSize in interface WriteStream<Buffer>
    
    Parameters:
    
    maxSize - the max size of the write stream
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - drainHandler
```
HttpServerResponse drainHandler(Handler<Void> handler)
```
    Description copied from interface: WriteStream
    
    Set a drain handler on the stream. If the write queue is full, then the handler will be called when the write queue has been reduced to maxSize / 2. See Pump for an example of this being used.
    
    Specified by:
    
    drainHandler in interface WriteStream<Buffer>
    
    Parameters:
    
    handler - the handler
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getStatusCode
```
int getStatusCode()
```
    Returns:
    
    the HTTP status code of the response. The default is 200 representing OK.
  - setStatusCode
```
HttpServerResponse setStatusCode(int statusCode)
```
    Set the status code. If the status message hasn't been explicitly set, a default status message corresponding to the code will be looked-up and used.
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getStatusMessage
```
String getStatusMessage()
```
    Returns:
    
    the HTTP status message of the response. If this is not specified a default value will be used depending on what setStatusCode(int) has been set to.
  - setStatusMessage
```
HttpServerResponse setStatusMessage(String statusMessage)
```
    Set the status message
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - setChunked
```
HttpServerResponse setChunked(boolean chunked)
```
    If chunked is true, this response will use HTTP chunked encoding, and each call to write to the body will correspond to a new HTTP chunk sent on the wire.
    If chunked encoding is used the HTTP header Transfer-Encoding with a value of Chunked will be automatically inserted in the response.
    If chunked is false, this response will not use HTTP chunked encoding, and therefore the total size of any data that is written in the respone body must be set in the Content-Length header before any data is written out.
    An HTTP chunked response is typically used when you do not know the total size of the request body up front.
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - isChunked
```
boolean isChunked()
```
    Returns:
    
    is the response chunked?
  - headers
```
MultiMap headers()
```
    Returns:
    
    The HTTP headers
  - putHeader
```
HttpServerResponse putHeader(String name,
                             String value)
```
    Put an HTTP header
    
    Parameters:
    
    name - the header name
    
    value - the header value.
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - putHeader
```
HttpServerResponse putHeader(CharSequence name,
                             CharSequence value)
```
    Like putHeader(String, String) but using CharSequence
  - putHeader
```
HttpServerResponse putHeader(String name,
                             Iterable<String> values)
```
    Like putHeader(String, String) but providing multiple values via a String Iterable
  - putHeader
```
HttpServerResponse putHeader(CharSequence name,
                             Iterable<CharSequence> values)
```
    Like putHeader(String, Iterable) but with CharSequence Iterable
  - trailers
```
MultiMap trailers()
```
    Returns:
    
    The HTTP trailers
  - putTrailer
```
HttpServerResponse putTrailer(String name,
                              String value)
```
    Put an HTTP trailer
    
    Parameters:
    
    name - the trailer name
    
    value - the trailer value
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - putTrailer
```
HttpServerResponse putTrailer(CharSequence name,
                              CharSequence value)
```
    Like putTrailer(String, String) but using CharSequence
  - putTrailer
```
HttpServerResponse putTrailer(String name,
                              Iterable<String> values)
```
    Like putTrailer(String, String) but providing multiple values via a String Iterable
  - putTrailer
```
HttpServerResponse putTrailer(CharSequence name,
                              Iterable<CharSequence> value)
```
    Like putTrailer(String, Iterable) but with CharSequence Iterable
  - closeHandler
```
HttpServerResponse closeHandler(Handler<Void> handler)
```
    Set a close handler for the response. This will be called if the underlying connection closes before the response is complete.
    
    Parameters:
    
    handler - the handler
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - write
```
HttpServerResponse write(String chunk,
                         String enc)
```
    Write a String to the response body, encoded using the encoding enc.
    
    Parameters:
    
    chunk - the string to write
    
    enc - the encoding to use
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - write
```
HttpServerResponse write(String chunk)
```
    Write a String to the response body, encoded in UTF-8.
    
    Parameters:
    
    chunk - the string to write
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - writeContinue
```
HttpServerResponse writeContinue()
```
    Used to write an interim 100 Continue response to signify that the client should send the rest of the request. Must only be used if the request contains an "Expect:100-Continue" header
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - end
```
void end(String chunk)
```
    Same as end(Buffer) but writes a String in UTF-8 encoding before ending the response.
    
    Parameters:
    
    chunk - the string to write before ending the response
  - end
```
void end(String chunk,
         String enc)
```
    Same as end(Buffer) but writes a String with the specified encoding before ending the response.
    
    Parameters:
    
    chunk - the string to write before ending the response
    
    enc - the encoding to use
  - end
```
void end(Buffer chunk)
```
    Same as end() but writes some data to the response body before ending. If the response is not chunked and no other data has been written then the @code{Content-Length} header will be automatically set.
    
    Specified by:
    
    end in interface WriteStream<Buffer>
    
    Parameters:
    
    chunk - the buffer to write before ending the response
  - end
```
void end()
```
    Ends the response. If no data has been written to the response body, the actual response won't get written until this method gets called.
    Once the response has ended, it cannot be used any more.
    
    Specified by:
    
    end in interface WriteStream<Buffer>
  - sendFile
```
default HttpServerResponse sendFile(String filename)
```
    Same as sendFile(String, long) using offset @code{0} which means starting from the beginning of the file.
    
    Parameters:
    
    filename - path to the file to serve
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - sendFile
```
default HttpServerResponse sendFile(String filename,
                                    long offset)
```
    Same as sendFile(String, long, long) using length @code{Long.MAX_VALUE} which means until the end of the file.
    
    Parameters:
    
    filename - path to the file to serve
    
    offset - offset to start serving from
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - sendFile
```
HttpServerResponse sendFile(String filename,
                            long offset,
                            long length)
```
    Ask the OS to stream a file as specified by filename directly from disk to the outgoing connection, bypassing userspace altogether (where supported by the underlying operating system. This is a very efficient way to serve files.
    The actual serve is asynchronous and may not complete until some time after this method has returned.
    
    Parameters:
    
    filename - path to the file to serve
    
    offset - offset to start serving from
    
    length - length to serve to
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - sendFile
```
default HttpServerResponse sendFile(String filename,
                                    Handler<AsyncResult<Void>> resultHandler)
```
    Like sendFile(String) but providing a handler which will be notified once the file has been completely written to the wire.
    
    Parameters:
    
    filename - path to the file to serve
    
    resultHandler - handler that will be called on completion
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - sendFile
```
default HttpServerResponse sendFile(String filename,
                                    long offset,
                                    Handler<AsyncResult<Void>> resultHandler)
```
    Like sendFile(String, long) but providing a handler which will be notified once the file has been completely written to the wire.
    
    Parameters:
    
    filename - path to the file to serve
    
    offset - the offset to serve from
    
    resultHandler - handler that will be called on completion
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - sendFile
```
HttpServerResponse sendFile(String filename,
                            long offset,
                            long length,
                            Handler<AsyncResult<Void>> resultHandler)
```
    Like sendFile(String, long, long) but providing a handler which will be notified once the file has been completely written to the wire.
    
    Parameters:
    
    filename - path to the file to serve
    
    offset - the offset to serve from
    
    length - the length to serve to
    
    resultHandler - handler that will be called on completion
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - close
```
void close()
```
    Close the underlying TCP connection corresponding to the request.
  - ended
```
boolean ended()
```
    Returns:
    
    has the response already ended?
  - closed
```
boolean closed()
```
    Returns:
    
    has the underlying TCP connection corresponding to the request already been closed?
  - headWritten
```
boolean headWritten()
```
    Returns:
    
    have the headers for the response already been written?
  - headersEndHandler
```
HttpServerResponse headersEndHandler(Handler<Void> handler)
```
    Provide a handler that will be called just before the headers are written to the wire.
    This provides a hook allowing you to add any more headers or do any more operations before this occurs.
    
    Parameters:
    
    handler - the handler
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - bodyEndHandler
```
HttpServerResponse bodyEndHandler(Handler<Void> handler)
```
    Provide a handler that will be called just before the last part of the body is written to the wire and the response is ended.
    This provides a hook allowing you to do any more operations before this occurs.
    
    Parameters:
    
    handler - the handler
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - bytesWritten
```
long bytesWritten()
```
    Returns:
    
    the total number of bytes written for the body of the response.

Interface HttpServerResponse

Method Summary

Methods inherited from interface io.vertx.core.streams.WriteStream

Method Detail

exceptionHandler

write

setWriteQueueMaxSize

drainHandler

getStatusCode

setStatusCode

getStatusMessage

setStatusMessage

setChunked

isChunked

headers

putHeader

putHeader

putHeader

putHeader

trailers

putTrailer

putTrailer

putTrailer

putTrailer

closeHandler

write

write

writeContinue

end

end

end

end

sendFile

sendFile

sendFile

sendFile

sendFile

sendFile

close

ended

closed

headWritten

headersEndHandler

bodyEndHandler

bytesWritten