Motivation:
The generics for the existing futures, promises, and listeners are too complicated.
This complication comes from the existence of `ChannelPromise` and `ChannelFuture`, which forces listeners to care about the particular _type_ of future being listened on.
Modification:
* Add a `FutureContextListener` which can take a context object as an additional argument. This allows our listeners to have the channel piped through to them, so they don't need to rely on the `ChannelFuture.channel()` method.
* Make the `FutureListener`, along with the `FutureContextListener` sibling, the default listener API, retiring the `GenericFutureListener` since we no longer need to abstract over the type of the future.
* Change all uses of `ChannelPromise` to `Promise<Void>`.
* Change all uses of `ChannelFuture` to `Future<Void>`.
* Change all uses of `GenericFutureListener` to either `FutureListener` or `FutureContextListener` as needed.
* Remove `ChannelFutureListener` and `GenericFutureListener`.
* Introduce a `ChannelFutureListeners` enum to house the constants that previously lived in `ChannelFutureListener`. These constants now implement `FutureContextListener` and take the `Channel` as a context.
* Remove `ChannelPromise` and `ChannelFuture` — all usages now rely on the plain `Future` and `Promise` APIs.
* Add static factory methods to `DefaultPromise` that allow us to create promises that are initialised as successful or failed.
* Remove `CompleteFuture`, `SucceededFuture`, `FailedFuture`, `CompleteChannelFuture`, `SucceededChannelFuture`, and `FailedChannelFuture`.
* Remove `ChannelPromiseNotifier`.
Result:
Cleaner generics and more straight forward code.
Motivation:
We didnt really have a good use-case for removeListener* and addListeners. Because of this we should just remove these methods and so make things simpler.
Modifications:
Remove methods
Result:
Cleanup
Motivation:
ParserImpl is stateless and so we can use the same instance multiple times
Modifications:
- Make constructor private
- Return the same instance all the time
Result:
Less object creation
Motivation:
DefaultHostsFileEntriesResolver should provide all hosts file's entries for a hostname when
DnsNameResolver#resolveAll as opposed to the current implementation where only the first
entry is taken into consideration
Modification:
- Add DefaultHostsFileEntriesResolver#addresses to provide all hosts file's entries for a hostname
- Add HostsFileEntriesProvider to provide all hosts file's entries for a hostname and to keep
backwards compatibility for HostsFileEntries and HostsFileParser
- DnsNameResolver#resolveAll uses the new DefaultHostsFileEntriesResolver#addresses
- BlockHound configuration: replace HostsFileParser#parse with HostsFileEntriesProvider$ParserImpl#parse
as the latter does the parsing
- Add junit tests
Result:
Fixes#10834
Motivation:
https in xmlns URIs does not work and will let the maven release plugin fail:
```
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.779 s
[INFO] Finished at: 2020-11-10T07:45:21Z
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-release-plugin:2.5.3:prepare (default-cli) on project netty-parent: Execution default-cli of goal org.apache.maven.plugins:maven-release-plugin:2.5.3:prepare failed: The namespace xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" could not be added as a namespace to "project": The namespace prefix "xsi" collides with an additional namespace declared by the element -> [Help 1]
[ERROR]
```
See also https://issues.apache.org/jira/browse/HBASE-24014.
Modifications:
Use http for xmlns
Result:
Be able to use maven release plugin
Motivation:
HTTP is a plaintext protocol which means that someone may be able
to eavesdrop the data. To prevent this, HTTPS should be used whenever
possible. However, maintaining using https:// in all URLs may be
difficult. The nohttp tool can help here. The tool scans all the files
in a repository and reports where http:// is used.
Modifications:
- Added nohttp (via checkstyle) into the build process.
- Suppressed findings for the websites
that don't support HTTPS or that are not reachable
Result:
- Prevent using HTTP in the future.
- Encourage users to use HTTPS when they follow the links they found in
the code.
Motivation:
LGTM reports multiple issues. They need to be triaged,
and real ones should be fixed.
Modifications:
- Fixed multiple issues reported by LGTM, such as redundant conditions,
resource leaks, typos, possible integer overflows.
- Suppressed false-positives.
- Added a few testcases.
Result:
Fixed several possible issues, get rid of false alarms in the LGTM report.
Motivation:
We should keep the scope of the synchronized block as small as possible.
Modifications:
Reduce scope by copy to an array first before iterate through it
Result:
Smaller scope of synchronized
Motivation:
When an `AddressResolverGroup` closes, it can leave unwanted listeners attached to its `EventExecutor`'s termination future.
Modifications:
- Keep track of listeners attached to termination futures
- Clear listeners if the `AddressResolverGroup` closes before its associated executor(s)
Result:
Unwanted listeners no longer remain in memory after an `AddressResolverGroup` closes before its associated executor(s).
Motivation:
The resolver API and implementations should be considered stable by now so we should not mark these with @UnstableApi
Modifications:
Remove @UnstableApi annotation from API and implementation of resolver
Result:
Make it explicit that the API is considered stable
Motivation:
RoundRobinDnsAddressResolverGroup ultimately opens UDP
ports for DNS resolution. Callers likely expect that
RoundRobinDnsAddressResolverGroup#close() will close those
ports, but that is not currently true (see #9212).
Modifications:
Overrode RoundRobinInetAddressResolver#close() to close
the delegate name resolver, which in turn closes any UDP
ports used for name resolution.
Result:
RoundRobinDnsAddressResolverGroup#close() closes UDP ports
as expected. This fixes#9212.
Motivation:
We can just use Objects.requireNonNull(...) as a replacement for ObjectUtil.checkNotNull(....)
Modifications:
- Use Objects.requireNonNull(...)
Result:
Less code to maintain.
Motivation:
We can use lambdas now as we use Java8.
Modification:
use lambda function for all package, #8751 only migrate transport package.
Result:
Code cleanup.
Motivation:
Custom Netty ThreadLocalRandom and ThreadLocalRandomProvider classes are no longer needed and can be removed.
Modification:
Remove own ThreadLocalRandom
Result:
Less code to maintain
Motivation:
We can use the diamond operator these days.
Modification:
Use diamond operator whenever possible.
Result:
More modern code and less boiler-plate.
Motivation:
In windows if the project is in a path that contains whitespace,
resources cannot be accessed and tests fail.
Modifications:
Adds ResourcesUtil.java in netty-common. Tests use ResourcesUtil.java to access a resource.
Result:
Being able to build netty in a path containing whitespace
Motivation:
We should support to parse and read a hosts file which is stored in a different encoding then the system default. Beside this when we are on windows we should just try to parse it with multiple different charset before giving up as there is no real standard what charset to use.
Modifications:
- Add more method overloads to HostsFileParser that take a Charset.
- Try to parse with multiple Charsets in DefaultHostsFileEntriesResolver when windows is used.
- Add unit test
Result:
Fixes https://github.com/netty/netty/issues/8208.
Motivation
There is a cost to concatenating strings and calling methods that will be wasted if the Logger's level is not enabled.
Modifications
Check if Log level is enabled before producing log statement. These are just a few cases found by RegEx'ing in the code.
Result
Tiny bit more efficient code.
