RFR (S) 8230407 : SocketPermission and FilePermission action list allows leading comma

[Peter Levart]

Hi Ivan,

On 10/1/19 10:26 PM, Ivan Gerasimov wrote:
> Hello!
>
> The constructors of SocketPermission and FilePermission expect a 
> String argument with comma-separated list of actions.
>
> If the list is malformed, then the constructors throw 
> IllegalArgumentException.
>
> It turns out that the current implementation fails to throw IAE if the 
> list starts with a leading comma.
>
> Would you please help review a simple fix, which will make the 
> behavior more consistent?
>
> BUGURL: https://bugs.openjdk.java.net/browse/JDK-8230407
> WEBREV: http://cr.openjdk.java.net/~igerasim/8230407/00/webrev/
>

With new switch expressions the logic could be a little clearer. For 
example:

             for (boolean seencomma = false; i >= matchlen && 
!seencomma; i--) {
                 seencomma = switch (a[i - matchlen]) {
                     case ' ', '\r', '\n', '\f', '\t': yield false;
                     case ',': if (i > matchlen) yield true;
                     default: throw new IllegalArgumentException(
                                 "invalid permission: " + actions);
                 };
             }


This is still experimental, but I think it will be proposed to be 
standard soon.

If you want to backport it later, then maybe you don't want to do that now.

Regards, Peter