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public class: ChunkedOutputStream [javadoc | source]

All Implemented Interfaces:
    Closeable, Flushable

This class implements chunked transfer coding as described in the Section 3.6.1 of RFC 2616. Writes are buffered to an internal buffer (2048 default size). Chunks are guaranteed to be at least as large as the buffer size (except for the last chunk).

3.6.1 Chunked Transfer Coding

The chunked encoding modifies the body of a message in order to transfer it as a series of chunks, each with its own size indicator, followed by an OPTIONAL trailer containing entity-header fields. This allows dynamically produced content to be transferred along with the information necessary for the recipient to verify that it has received the full message.

 Chunked-Body   = *chunk

 chunk          = chunk-size [ chunk-extension ] CRLF
                  chunk-data CRLF
 chunk-size     = 1*HEX
 last-chunk     = 1*("0") [ chunk-extension ] CRLF

 chunk-extension= *( ";" chunk-ext-name [ "=" chunk-ext-val ] )
 chunk-ext-name = token
 chunk-ext-val  = token | quoted-string
 chunk-data     = chunk-size(OCTET)
 trailer        = *(entity-header CRLF)

The chunk-size field is a string of hex digits indicating the size of the chunk. The chunked encoding is ended by any chunk whose size is zero, followed by the trailer, which is terminated by an empty line.

The trailer allows the sender to include additional HTTP header fields at the end of the message. The Trailer header field can be used to indicate which header fields are included in a trailer (see section 14.40).

A server using chunked transfer-coding in a response MUST NOT use the trailer for any header fields unless at least one of the following is true:

a)the request included a TE header field that indicates "trailers" is acceptable in the transfer-coding of the response, as described in section 14.39; or,

b)the server is the origin server for the response, the trailer fields consist entirely of optional metadata, and the recipient could use the message (in a manner acceptable to the origin server) without receiving this metadata. In other words, the origin server is willing to accept the possibility that the trailer fields might be silently discarded along the path to the client.

This requirement prevents an interoperability failure when the message is being received by an HTTP/1.1 (or later) proxy and forwarded to an HTTP/1.0 recipient. It avoids a situation where compliance with the protocol would have necessitated a possibly infinite buffer on the proxy.

 public ChunkedOutputStream(HttpDataTransmitter datatransmitter) throws IOException 
    Wraps a data transmitter and chunks the output. The default buffer size of 2048 was chosen because the chunk overhead is less than 0.5%
    datatransmitter - the transmitter to wrap
    IOException -
 public ChunkedOutputStream(HttpDataTransmitter out,
    int bufferSize) throws IOException 
    Wraps a stream and chunks the output.
    out - the transmitter to wrap
    bufferSize - minimum chunk size (excluding last chunk)
    IOException -
    since: 3.0 -
Method from org.apache.http.io.ChunkedOutputStream Summary:
close,   finish,   flush,   flushCache,   flushCacheWithAppend,   write,   write,   write,   writeClosingChunk
Methods from java.io.OutputStream:
close,   flush,   write,   write,   write
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.http.io.ChunkedOutputStream Detail:
 public  void close() throws IOException 
    Finishes writing to the underlying stream, but does NOT close the underlying stream.
 public  void finish() throws IOException 
    Must be called to ensure the internal cache is flushed and the closing chunk is written.
 public  void flush() throws IOException 
    Flushes the underlying stream, but leaves the internal buffer alone.
 protected  void flushCache() throws IOException 
    Writes the cache out onto the underlying stream
 protected  void flushCacheWithAppend(byte[] bufferToAppend,
    int off,
    int len) throws IOException 
    Writes the cache and bufferToAppend to the underlying stream as one large chunk
 public  void write(int b) throws IOException 
 public  void write(byte[] b) throws IOException 
    Writes the array. If the array does not fit within the buffer, it is not split, but rather written out as one large chunk.
 public  void write(byte[] src,
    int off,
    int len) throws IOException 
 protected  void writeClosingChunk() throws IOException