Code Review Request: 7168172: (fs) Files.isReadable slow on Windows

[Zhong Yu]

Ulf you are right.

Question about release schedule: will this fix be included in a jdk7 release?

On Thu, Aug 23, 2012 at 7:53 AM, Ulf Zibis <Ulf.Zibis at gmx.de> wrote:
> Am 23.08.2012 01:50, schrieb Zhong Yu:
>>>
>>>      public void checkAccess(Path obj, AccessMode... modes) throws
>>>
>>> IOException {
>>>          AccessMode r = null;
>>>          AccessMode w = null;
>>>          AccessMode x = null;
>>>          for (AccessMode mode: modes) {
>>>              switch (mode) {
>>>                  case READ : r = READ; break;
>>>                  case WRITE : w = WRITE; break;
>>>                  case EXECUTE : x = EXECUTE; break;
>>>                  default: throw new AssertionError("Should not get
>>> here");
>>>              }
>>>          }
>>
>> That'll leave r==null if `modes` is empty. But an empty `modes` is
>> supposed to be equivalent to [READ].
>
>
> Yes, but in that case w and x are also null, so the "special-case read
> access" will be invoked anyway, and the null-ness of r wouldn't matter.
>
>>>          WindowsPath file = WindowsPath.toWindowsPath(obj);
>>>
>>>          // special-case read access to avoid needing to determine
>>> effective
>>>          // access to file
>>>          if (w == null && x == null) {
>>>              tryReadAccess(file);
>>>              return;
>>>          }
>>>
>>>          ...
>>>      }
>>>
>>> -Ulf
>>>
>