RFR 8198997: Cache normalized/resolved user.dir property

[Claes Redestad]

Hi,

mixing volatiles and non-volatiles fields that are read and written to 
outside of
synchronized makes me somewhat queasy...

Instead of a volatile boolean and a mutable userDir field, couldn't this 
just
as well be modelled as:

- keep userDir final (always the not normalized value of 
System.getProperty("user.dir"))
- replace volatile boolean isUserDirNormal with volatile String 
normalizedUserDir
- then implement the DCL in getUserPath like:

String normalizedUserDir = this.normalizedUserDir;
if (normalizedUserDir == null) {
     synchronized(userDir) {
         if (normalizedUserDir == null) {
             normalizedUserDir = this.normalizedUserDir = 
normalize(userDir);
         }
     }
}
return normalizedUserDir;

WDYT?

/Claes

On 2018-03-12 19:32, Brian Burkhalter wrote:
> https://bugs.openjdk.java.net/browse/JDK-8198997
> http://cr.openjdk.java.net/~bpb/8198997/webrev.00/
>
> Lazily cache the value of the user.dir property on first access. This change is for Windows only as there does not appear to be any percentage in doing something similar on Unix.
>
> Thanks,
>
> Brian