Review request for 7034570 - java.lang.Runtime.exec(String[] cmd, String[] env) can not work properly if SystemRoot not inherited

[Ulf Zibis]

Oops, I was irritated by the internal int variables, but yes, they reside on stack, so no worry 
about thread-safety.

-Ulf


Am 18.04.2011 20:16, schrieb David Schlosnagle:
> On Mon, Apr 18, 2011 at 1:40 PM, Ulf Zibis<Ulf.Zibis at gmx.de>  wrote:
>> Am 15.04.2011 15:43, schrieb Michael McMahon:
>>> I have incorporated much of Ulf's approach into this version.
>>>
>>> I agree with Alan about the spec. We could find other variables in the
>>> future that need
>>> to be set, but can have alternative values other than the default. I think
>>> this approach
>>> is the most flexible.
>>>
>>> http://cr.openjdk.java.net/~michaelm/7034570/webrev.4/
>>>
>> Additionally I see another problem:
>>
>> Because the ProcessEnvironment.nameComparator is static, creating a new
>> Process will not be thread-safe!
> Ulf,
>
> I don't see a problem here. The ProcessEnvironment.nameComparator is a
> static final field that is initialized to `new NameComparator()` in a
> static initialization block for the ProcessEnvironment class. The
> NameComparator has no instance state, and can be safely shared by
> multiple threads.
>
> > From http://cr.openjdk.java.net/~michaelm/7034570/webrev.4/src/windows/classes/java/lang/ProcessEnvironment.java.html:
>   191     private static final class NameComparator
>   192         implements Comparator<String>  {
>   193         public int compare(String s1, String s2) {
>   194             // We can't use String.compareToIgnoreCase since it
>   195             // canonicalizes to lower case, while Windows
>   196             // canonicalizes to upper case!  For example, "_" should
>   197             // sort *after* "Z", not before.
>   198             int n1 = s1.length();
>   199             int n2 = s2.length();
>   200             int min = Math.min(n1, n2);
>   201             for (int i = 0; i<  min; i++) {
>   202                 char c1 = s1.charAt(i);
>   203                 char c2 = s2.charAt(i);
>   204                 if (c1 != c2) {
>   205                     c1 = Character.toUpperCase(c1);
>   206                     c2 = Character.toUpperCase(c2);
>   207                     if (c1 != c2)
>   208                         // No overflow because of numeric promotion
>   209                         return c1 - c2;
>   210                 }
>   211             }
>   212             return n1 - n2;
>   213         }
>   214     }
> ...
>   227     private static final NameComparator nameComparator;
> ...
>   233     static {
>   234         nameComparator  = new NameComparator();
> ...
>
> - Dave
>