RFR: 8263233: Update java.net and java.nio to use instanceof pattern variable [v3]

[Mark Sheppard]

On Tue, 9 Mar 2021 19:56:25 GMT, Patrick Concannon <pconcannon at openjdk.org> wrote:

>> Hi,
>> 
>> Could someone please review my code for updating the code in the `java.net` and `java.nio` packages to make use of the `instanceof` pattern variable?
>> 
>> Kind regards,
>> Patrick
>
> Patrick Concannon has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8263233: Refactored equals method further

src/java.base/share/classes/java/net/NetMulticastSocket.java line 219:

> 217:         if (addr == null)
> 218:             addr = new InetSocketAddress(0);
> 219:         if (!(addr instanceof InetSocketAddress epoint))

in the context of this type of change the negative logic is a little obtuse or disjoint in the new style variable declaration, and its subsequent use. I'd find it a more natural flow and easier to read with the instance pattern prefacing a block in which the variable is used
if (addr instanced InetSocketAddress epoint) {
  // a block which is using the epoint variable
   if (epoint.isUnresolved)
      throw new SocketException("Unresolved address");
   InetAddress iaddr = epoint.getAddress;
 etc, etc ...
} else {
   throw new IllegalArgumentException("Unsupported address type!");
}

-------------

PR: https://git.openjdk.java.net/jdk/pull/2890