Motivation:
ByteToMessageDecoder requires using an intermediate List to put results into. This intermediate list adds overhead (memory/CPU) which grows as the number of objects increases. This overhead can be avoided by directly propagating events through the ChannelPipeline via ctx.fireChannelRead(...). This also makes the semantics more clear and allows us to keep track if we need to call ctx.read() in all cases.
Modifications:
- Remove List from the method signature of ByteToMessageDecoder.decode(...) and decodeLast(...)
- Adjust all sub-classes
- Adjust unit tests
- Fix javadocs.
Result:
Adjust ByteToMessageDecoder as noted in https://github.com/netty/netty/issues/8525.
Motivation:
We should use Objects.requireNonNull(...) as we require java8
Modifications:
Replace ObjectUtil.checkNonNull(...) with Objects.requireNonNull(...)
Result:
Code cleanup
Motivation:
We can replace some "hand-rolled" integer checks with our own static utility method to simplify the code.
Modifications:
Use methods provided by `ObjectUtil`.
Result:
Cleaner code and less duplication
Motivation:
When decoding stomp frames a lot of unnecessary character arrays are created when parsing headers.
For every header, an array is created to read the line into and then more when splitting the line at the colon.
Modifications:
Parse key and value of a header while reading the line instead of afterwards.
Reuse a single AppendableCharSequence.
Reduce initial size of AppendableCharSequence when reading the command as it is expected to be short.
Result:
Allocations when parsing stomp frames have dropped significantly.
Motivation:
By STOMP 1.2 specification - header name or value include any octet except CR or LF or ":".
Modification:
Add constructor argument that allows to enable / disable validation.
Result:
Fixes [#7083]
Motivation:
The STOMP decoder used to fail when parsing a frame with no content-length
and a body split across multiple packets.
Modifications:
Support contentLength of -1 (indicating indeterminate length) and added a
check to getContentLength. Moved the NUL byte searching from the
readHeaders() method out to the main decoder loop.
Result:
A STOMP frame can be properly parsed even if it's missing the
content-length header and the NUL byte is in a later packet.
Motivation:
The header class hierarchy and algorithm was improved on the master branch for versions 5.x. These improvments should be backported to the 4.1 baseline.
Modifications:
- cherry-pick the following commits from the master branch: 2374e17, 36b4157, 222d258
Result:
Header improvements in master branch are available in 4.1 branch.
Modifications:
- Added a static modifier for CompositeByteBuf.Component.
This class is an inner class, but does not use its embedded reference to the object which created it. This reference makes the instances of the class larger, and may keep the reference to the creator object alive longer than necessary.
- Removed unnecessary boxing/unboxing operations in HttpResponseDecoder, RtspResponseDecoder, PerMessageDeflateClientExtensionHandshaker and PerMessageDeflateServerExtensionHandshaker
A boxed primitive is created from a String, just to extract the unboxed primitive value.
- Removed unnecessary 3 times calculations in DiskAttribute.addContent(...).
- Removed unnecessary checks if file exists before call mkdirs() in NativeLibraryLoader and PlatformDependent.
Because the method mkdirs() has this check inside.
- Removed unnecessary `instanceof AsciiString` check in StompSubframeAggregator.contentLength(StompHeadersSubframe) and StompSubframeDecoder.getContentLength(StompHeaders, long).
Because StompHeaders.get(CharSequence) always returns java.lang.String.
Motivation:
We have quite a bit of code duplication between HTTP/1, HTTP/2, SPDY,
and STOMP codec, because they all have a notion of 'headers', which is a
multimap of string names and values.
Modifications:
- Add TextHeaders and its default implementation
- Add AsciiString to replace HttpHeaderEntity
- Borrowed some portion from Apache Harmony's java.lang.String.
- Reimplement HttpHeaders, SpdyHeaders, and StompHeaders using
TextHeaders
- Add AsciiHeadersEncoder to reuse the encoding a TextHeaders
- Used a dedicated encoder for HTTP headers for better performance
though
- Remove shortcut methods in SpdyHeaders
- Replace SpdyHeaders.getStatus() with HttpResponseStatus.parseLine()
Result:
- Removed quite a bit of code duplication in the header implementations.
- Slightly better performance thanks to improved header validation and
hash code calculation
