Notice: This is expected to be the last version supporting Java 6. Comment on #3961 if this causes you trouble. Android API level 14 support will be unchanged.

Dependencies

• Updated to Netty 4.1.27 and Netty TCNative 2.0.12

• gRPC is now regularly tested with JDK 9 and 10

• Warning, a bug was discovered after this release where using Netty Epoll would increase memory usage. Please avoid this release of gRPC if you know you use Netty Epoll

API Changes

• OkHttpChannelBuilder#negotiationType is now deprecated
• Made protobuf, protobuf-lite, and protobuf-nano classes final.

New Features

• Channel Tracing now record State Changes
• Stubs now have an RpcMethod annotation for use with annotation processors
• Added support for providing List<EquivalentAddressGroup> to LoadBalancer Subchannels, in addition to the option of providing a EquivalentAddressGroup (EAG). This prevents the need for LoadBalancers to "flatten" a List<EquivalentAddressGroup> into a single EquivalentAddressGroup which loses/confuses the EAG's Attributes. NameResolvers can now specify Attributes in an EAG and expect that the values are passed to gRPC's core. Future work will add List<EAG> for OobChannels.
• InProcessSocketAddress now has a useful toString() method
• AndroidChannelBuilder is now easier to build
• RoundRobinLoadBalancer now scales better when using stickiness

Behavior Changes

• gRPCLB no longer depends on having a Service Config

Bug Fixes

• Fix regression that broke Java 9 ALPN support. This fixes the error "SunJSSE selected, but Jetty NPN/ALPN unavailable" (#4620)
• Fixed a bug with gRPC LB parsing SRV DNS records ( 6dbe392 )
• enterIdle() will exit idle mode if channel is still in use (#4665)
• TransmitStatusRuntimeExceptionInterceptor now avoids accidentally double closing the call.

Documentation

• Clarified StreamObserver interaction with thread safety

Thanks to all our Contributors:

• @DmPanov
• @groakley - Grant Oakley
• @jbingham-google - Jonathan Bingham
• @jyane - Shohei Kamimori
• @kay - Doug Lawrie
• @marcoferrer - Marco Ferrer
• @njhill - Nick Hill
• @punkeel - Maxime Guerreiro
• @songya - Yang Song
• @sullis
• @werkt - George Gensure