private String simpleMethodName() {
        String simpleMethodName = simpleMethodNames.get(method);
        if (simpleMethodName == null) {
            simpleMethodName = method.getBareMethodName();
        }
        return simpleMethodName;
    }
Encapsulates the state of a single client call, writing messages from the client and reading responses
from the server, passing to business logic via {@link ClientCall.Listener}.
grpc/src/main/java/com/linecorp/armeria/internal/client/grpc/ArmeriaClientCall.java