[OpenJDK 2D-Dev] RFR: 8263311: Watch registry changes for remote printers update instead of polling

[Prasanta Sadhukhan]

On Wed, 10 Mar 2021 15:38:27 GMT, Alexey Ivanov <aivanov at openjdk.org> wrote:

> [JDK-8153732](https://bugs.openjdk.java.net/browse/JDK-8153732) implemented polling for remote printers.
> That bug description also mentions watching the registry for changes and links to the article which describes the method yet it does so in terms of WMI. Using WMI is not necessary to watch for the registry updates.
> 
> It is possible to replace polling mechanism with registry change notifications. If the registry at `HKCU\Printers\Connections` is updated, refresh the list of print services.
> 
> It works perfectly well in my own testing with sharing a Generic / Text Only printer from another laptop. The notification comes as soon as the printer is installed, it results in a new key created under `Connections`. If a remote printer is removed, the notification is also triggered as the key corresponding to that printer is removed from the registry.
> 
> I updated the steps in the manual test: `RemotePrinterStatusRefresh.java`.

Marked as reviewed by psadhukhan (Reviewer).

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PR: https://git.openjdk.java.net/jdk/pull/2915