I2PTunnelHTTPServer.CompressedResponseOutputStream

net.i2p.i2ptunnel.I2PTunnelHTTPServer.CompressedResponseOutputStream

All Implemented Interfaces:: Closeable, Flushable, AutoCloseable

Enclosing class:: I2PTunnelHTTPServer

private static class I2PTunnelHTTPServer.CompressedResponseOutputStreamextends HTTPResponseOutputStream

Gzips the response on its way to the browser.

Field Summary
Fields
Modifier and Type
Field
Description
private GZIPOutputStream
_gzipOut
The gzip stream for the response.
private final String
_requestHeaders
Request headers used to judge compression.
private static final Set<String>
COMPRESSED_TYPES
Content types that are already compressed; skip re-compression.
Fields inherited from class HTTPResponseOutputStream
_contentEncoding, _contentType, _dataExpected, _gzip, _headerBuffer, _keepAliveIn, _keepAliveOut
Modifier and Type
Field
Description
protected String
_contentEncoding
Response Content-Encoding header value, lower-case and trimmed.
protected String
_contentType
Response Content-Type header value, lower-case and trimmed.
protected long
_dataExpected
Content-Length of the body in bytes, -1 if unknown or chunked, 0 for a bodyless response.
protected boolean
_gzip
Set when the response carries Content-Encoding: x-i2p-gzip, so the body is gunzipped.
protected ByteArray
_headerBuffer
Pooled buffer holding the response header block while it is parsed, null once emitted.
protected boolean
_keepAliveIn
True if the outproxy (I2P) side connection may be reused after this response.
protected boolean
_keepAliveOut
True if the browser side socket may be reused after this response.
Fields inherited from class FilterOutputStream
out
Constructor Summary
Constructors
Constructor
Description
CompressedResponseOutputStream(OutputStream o, boolean keepalive, String requestHeaders)
Create a compressed response output stream.
Method Summary
Public Methods
Modifier and Type
Method
Description
protected void
beginProcessing()
Wrap the output stream with gzip compression if compression is enabled.
void
finish()
Finish gzipping but don't close the output stream if keepalive is true.
protected void
finishHeaders()
Write the Content-Encoding header if compression is enabled.
protected boolean
shouldCompress()
Determine if the response should be gzip-compressed.
Methods inherited from class HTTPResponseOutputStream
canRangeResume, clearTransientResumeFailure, close, getBodyReceived, getDataExpected, getHeaderWritten, getKeepAliveIn, getKeepAliveOut, isTransientResumeFailure, prepareBodyResume, write, write
Modifier and Type
Method
Description
boolean
canRangeResume()
Whether a Content-Length body can be safely spliced with Range resume: headers written, a positive Content-Length, some body still missing, and no transparent gzip decode (which would desync the Range offset from wire bytes).
void
clearTransientResumeFailure()
Clear the transient-failure flag after the resume loop has observed it (budget refund / non-Range fallback decided).
void
close()
Release the pooled header buffer and close the underlying stream.
long
getBodyReceived()
Entity-body bytes forwarded to the browser after the first headers.
long
getDataExpected()
Original response Content-Length, or -1 if unknown/chunked/HEAD-empty.
boolean
getHeaderWritten()
Whether the first response header block has been written to the browser.
boolean
getKeepAliveIn()
Should we keep the input stream alive when done?
boolean
getKeepAliveOut()
Should we keep the output stream alive when done? Only supported for the browser socket side.
boolean
isTransientResumeFailure()
True when a transient status (408/502/503/504) aborted a Range resume.
void
prepareBodyResume()
Enter mid-body resume mode: the next header block parsed from a fresh tunnel is consumed for bookkeeping only and must not be written to the browser (the original status line and Content-Length were already sent).
void
write(byte[] buf, int off, int len)
Buffer bytes into the header block until the blank line arrives, then write the header out and forward the remaining bytes as the entity body.
void
write(int c)
Write a single byte, buffering it until the header block is complete.
Methods inherited from class FilterOutputStream
flush, write
Methods inherited from class OutputStream
nullOutputStream
Methods inherited from class Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details
- _gzipOut
  private GZIPOutputStream _gzipOut
  The gzip stream for the response.
- _requestHeaders
  private final String _requestHeaders
  Request headers used to judge compression.
- COMPRESSED_TYPES
  private static final Set<String> COMPRESSED_TYPES
  Content types that are already compressed; skip re-compression.
Constructor Details
- CompressedResponseOutputStream
  public CompressedResponseOutputStream(OutputStream o, boolean keepalive, String requestHeaders)
  Create a compressed response output stream.
  Parameters:
  o - the underlying output stream
  keepalive - if true, don't close the stream on finish
  requestHeaders - the HTTP request headers for Accept-Encoding check
Method Details
- finish
  public void finish() throws IOException
  Finish gzipping but don't close the output stream if keepalive is true. Overridden to peek at response code. Always returns line.
  Throws:
  IOException - if finishing the gzip stream fails
- shouldCompress
  protected boolean shouldCompress()
  Determine if the response should be gzip-compressed. Skips small responses, images, audio, video, and already-compressed formats. Compression is inline on the server side, decompression on the client side, so we avoid re-compressing formats that are already compressed.
  Overrides:
  shouldCompress in class HTTPResponseOutputStream
  Returns:
  true if the response should be compressed
- finishHeaders
  protected void finishHeaders() throws IOException
  Write the Content-Encoding header if compression is enabled.
  Overrides:
  finishHeaders in class HTTPResponseOutputStream
  Throws:
  IOException - if writing the header fails
- beginProcessing
  protected void beginProcessing() throws IOException
  Wrap the output stream with gzip compression if compression is enabled.
  Overrides:
  beginProcessing in class HTTPResponseOutputStream
  Throws:
  IOException - if creating the gzip stream fails

Field Summary

Fields inherited from class HTTPResponseOutputStream

Fields inherited from class FilterOutputStream

Constructor Summary

Method Summary

Methods inherited from class HTTPResponseOutputStream

Methods inherited from class FilterOutputStream

Methods inherited from class OutputStream

Methods inherited from class Object

Field Details

_gzipOut

_requestHeaders

COMPRESSED_TYPES

Constructor Details

CompressedResponseOutputStream

Method Details

finish

shouldCompress

finishHeaders

beginProcessing