Are GRPC support server sends messages to the client driving？

Hello everyone,sometimes I want to send something from server to client directly,not response by client call request,whether GRPC supports such operations currently？

The issue names no files, tests, or entry points. First determine whether server-initiated messages to clients are supported by the Java gRPC implementation; done would require a clearly scoped implementation or documentation change, but the requested behavior and acceptance criteria are not specified.

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