Heads-up for Java LoadBalancer major API change

[Kun Zhang]

If you don't implement your own gRPC Java LoadBalancer, you can stop reading now.

Dear gRPC users,

The experimental LoadBalancer interface will be soon replaced by what is currently LoadBalancer2. More details about the new API can be found in the design doc.

What's now LoadBalancer2 will be renamed to LoadBalancer, and the current LoadBalancer will be deleted. It will happen on master after the upcoming 1.1 release. The 1.1 release will not be impacted.

If you have your own LoadBalancer implementations, please start to migrate to the new API, because ManagedChannelBuilder.loadBalancerFactory() will stop accepting the old LoadBalancer API.

All the stock LoadBalancer implementations that come with gRPC will automatically be migrated to the new API. If your code only passes them to ManagedChannelBuilder.loadBalancerFactory(), you don't need to make any changes.

If you have any concerns, please reach out to me.

Thanks,

Kun

[Kun Zhang]

We have come up with a more concrete plan for the API and implementation migration.

You can find it on https://github.com/grpc/grpc-java/issues/2656

It will be updated with the progress.