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Author: ralf0131

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/Result.java

@@ -25,7 +25,14 @@
 
 
 /**
- * RPC invoke result. (API, Prototype, NonThreadSafe)
+ * (API, Prototype, NonThreadSafe)
+ *
+ * An RPC {@link Result}.
+ *
+ * Known implementations are:
+ * 1. {@link AsyncRpcResult}, it's a {@link CompletionStage} whose underlying value signifies the return value of an RPC call.
+ * 2. {@link AppResponse}, it inevitably inherits {@link CompletionStage} and {@link Future}, but you should never treat AppResponse as a type of Future,
+ *    instead, it is a normal concrete type.
  *
  * @serial Don't change the class name and package name.
  * @see org.apache.dubbo.rpc.Invoker#invoke(Invocation)