The JAR tool has an inconsistency with the extract (x) option on WIN32.
Notice when creating a JAR that the verbose output shows filenames in UNIX style format.
Notice when listing a JAR that the verbose output shows filesnames in UNIX style format.
Notice when extracting a JAR that the verbose output shows filenames in WIN32 style format.
This is inconsistent.

In the following examples I am using the MKS Toolkit with the Korn Shell on WIN32.

Also notice you can create a JAR on WIN32 using UNIX style and WIN32 style filenames for example:
% jar -cvf jar.jar dir/Neko2.java does work
% jar -cvf jar.jar dir\\Neko2.java does work

On the other hand you cannot extract files on WIN32 using UNIX style filenames but only WIN32 style filenames for example:
% jar -xvf jar.jar dir/Neko2.java does not work
% jar -xvf jar.jar dir\\Neko2.java does work

This is the problem. With extract the JAR tool should handle UNIX style and WIN32 style filenames
on WIN32 as it does with create.

This bug causes my JAR test suite to fail.

In summary:
(1) The verbose output for the extract option (x) should print out UNIX style filenames with "/" to be consistent with the create (c) and list (t) options.

(2) The extract option (x) should accept UNIX style filenames as well as WIN32 style filenames as part of the extract option so "jar -xvf jar.jar dir/Neko2.java" should work just like "jar -xvf jar.jar dir\\Neko2.java" does.

% jar -cvf jar.jar dir
adding: dir/ (in=0) (out=0) (stored 0%)
adding: dir/images/ (in=0) (out=0) (stored 0%)
adding: dir/images/SCCS/ (in=0) (out=0) (stored 0%)
adding: dir/images/SCCS/s.awake.gif (in=537) (out=398) (deflated 25%)
adding: dir/images/SCCS/s.stop.gif (in=573) (out=400) (deflated 30%)
adding: dir/images/SCCS/s.right1.gif (in=577) (out=399) (deflated 30%)
adding: dir/images/SCCS/s.right2.gif (in=585) (out=408) (deflated 30%)
adding: dir/images/SCCS/s.scratch1.gif (in=593) (out=415) (deflated 30%)
adding: dir/images/SCCS/s.scratch2.gif (in=585) (out=408) (deflated 30%)
adding: dir/images/SCCS/s.sleep1.gif (in=512) (out=375) (deflated 26%)
adding: dir/images/SCCS/s.sleep2.gif (in=522) (out=386) (deflated 26%)
adding: dir/images/SCCS/s.yawn.gif (in=581) (out=409) (deflated 29%)
adding: dir/images/right1.gif (in=136) (out=141) (deflated -3%)
adding: dir/images/awake.gif (in=152) (out=157) (deflated -3%)
adding: dir/images/yawn.gif (in=142) (out=147) (deflated -3%)
adding: dir/images/stop.gif (in=138) (out=143) (deflated -3%)
adding: dir/images/right2.gif (in=142) (out=145) (deflated -2%)
adding: dir/images/scratch1.gif (in=146) (out=151) (deflated -3%)
adding: dir/images/scratch2.gif (in=141) (out=146) (deflated -3%)
adding: dir/images/sleep1.gif (in=135) (out=140) (deflated -3%)
adding: dir/images/sleep2.gif (in=141) (out=146) (deflated -3%)
adding: dir/SCCS/ (in=0) (out=0) (stored 0%)
adding: dir/SCCS/s.Neko2$1.class (in=1534) (out=997) (deflated 35%)
adding: dir/SCCS/s.Neko2$2.class (in=1538) (out=996) (deflated 35%)
adding: dir/SCCS/s.Neko2.class (in=6298) (out=3455) (deflated 45%)
adding: dir/SCCS/s.Neko2.html (in=447) (out=286) (deflated 36%)
adding: dir/SCCS/s.Neko2.java (in=5856) (out=1783) (deflated 69%)
adding: dir/SCCS/s.ScrollingTextThread.class (in=3526) (out=2065) (deflated 41%)
adding: dir/Neko2.class (in=4336) (out=2389) (deflated 44%)
adding: dir/Neko2$1.class (in=879) (out=544) (deflated 38%)
adding: dir/Neko2$2.class (in=880) (out=545) (deflated 38%)
adding: dir/Neko2.html (in=130) (out=98) (deflated 24%)
adding: dir/Neko2.java (in=5539) (out=1605) (deflated 71%)
adding: dir/ScrollingTextThread.class (in=2314) (out=1360) (deflated 41%)

% jar -tvf jar.jar
  2313 Wed Jan 21 11:34:56 EST 1998 META-INF/MANIFEST.MF
     0 Tue Jan 20 12:31:44 EST 1998 dir/
     0 Tue Jan 20 12:31:42 EST 1998 dir/images
     0 Tue Jan 20 12:31:42 EST 1998 dir/images/SCCS/
   537 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.awake.gif
   573 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.stop.gif
   577 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.right1.gif
   585 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.right2.gif
   593 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.scratch1.gif
   585 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.scratch2.gif
   512 Tue Jan 20 12:31:40 EST 1998 dir/images/SCCS/s.sleep1.gif
   522 Tue Jan 20 12:31:42 EST 1998 dir/images/SCCS/s.sleep2.gif
   581 Tue Jan 20 12:31:42 EST 1998 dir/images/SCCS/s.yawn.gif
   136 Tue Jan 20 12:31:40 EST 1998 dir/images/right1.gif
   152 Tue Jan 20 12:31:40 EST 1998 dir/images/awake.gif
   142 Tue Jan 20 12:31:42 EST 1998 dir/images/yawn.gif
   138 Tue Jan 20 12:31:40 EST 1998 dir/images/stop.gif
   142 Tue Jan 20 12:31:40 EST 1998 dir/images/right2.gif
   146 Tue Jan 20 12:31:40 EST 1998 dir/images/scratch1.gif
   141 Tue Jan 20 12:31:42 EST 1998 dir/images/scratch2.gif
   135 Tue Jan 20 12:31:42 EST 1998 dir/images/sleep1.gif
   141 Tue Jan 20 12:31:42 EST 1998 dir/images/sleep2.gif
     0 Tue Jan 20 12:31:42 EST 1998 dir/SCCS/
  1534 Tue Jan 20 12:31:42 EST 1998 dir/SCCS/s.Neko2$1.class
  1538 Tue Jan 20 12:31:42 EST 1998 dir/SCCS/s.Neko2$2.class
  6298 Tue Jan 20 12:31:42 EST 1998 dir/SCCS/s.Neko2.class
   447 Tue Jan 20 12:31:42 EST 1998 dir/SCCS/s.Neko2.html
  5856 Tue Jan 20 12:31:42 EST 1998 dir/SCCS/s.Neko2.java
  3526 Tue Jan 20 12:31:44 EST 1998 dir/SCCS/s.ScrollingTextThread.class
  4336 Tue Jan 20 12:31:42 EST 1998 dir/Neko2.class
   879 Tue Jan 20 12:31:42 EST 1998 dir/Neko2$1.class
   880 Tue Jan 20 12:31:42 EST 1998 dir/Neko2$2.class
   130 Tue Jan 20 12:31:42 EST 1998 dir/Neko2.html
  5539 Tue Jan 20 12:31:44 EST 1998 dir/Neko2.java
  2314 Tue Jan 20 12:31:44 EST 1998 dir/ScrollingTextThread.class

Notice that the extract (x) output prints out filenames in WIN32 filename format using "\". It should print out using UNIX filename format using "/" to be consistent with create (c) and listing (t) options.
% jar -xvf jar.jar
 extracted: META-INF\MANIFEST.MF
   created: dir created: dir\images created: dir\images\SCCS extracted: dir\images\SCCS\s.awake.gif
 extracted: dir\images\SCCS\s.stop.gif
 extracted: dir\images\SCCS\s.right1.gif
 extracted: dir\images\SCCS\s.right2.gif
 extracted: dir\images\SCCS\s.scratch1.gif
 extracted: dir\images\SCCS\s.scratch2.gif
 extracted: dir\images\SCCS\s.sleep1.gif
 extracted: dir\images\SCCS\s.sleep2.gif
 extracted: dir\images\SCCS\s.yawn.gif
 extracted: dir\images\right1.gif
 extracted: dir\images\awake.gif
 extracted: dir\images\yawn.gif
 extracted: dir\images\stop.gif
 extracted: dir\images\right2.gif
 extracted: dir\images\scratch1.gif
 extracted: dir\images\scratch2.gif
 extracted: dir\images\sleep1.gif
 extracted: dir\images\sleep2.gif
   created: dir\SCCS extracted: dir\SCCS\s.Neko2$1.class
 extracted: dir\SCCS\s.Neko2$2.class
 extracted: dir\SCCS\s.Neko2.class
 extracted: dir\SCCS\s.Neko2.html
 extracted: dir\SCCS\s.Neko2.java
 extracted: dir\SCCS\s.ScrollingTextThread.class
 extracted: dir\Neko2.class
 extracted: dir\Neko2$1.class
 extracted: dir\Neko2$2.class
 extracted: dir\Neko2.html
 extracted: dir\Neko2.java
 extracted: dir\ScrollingTextThread.class

Notice that trying to extract (x) a file specified using UNIX filename format does not work. It should work because you can create (c) using UNIX filename format.
% jar -xvf jar.jar dir/Neko2.java

The following works on WIN32 using WIN32 filename style format.
% jar -xvf jar.jar dir\\Neko2.java
 extracted: dir\Neko2.java

In summary you should be able to extract files on WIN32 using either UNIX filename format or WIN32 filename format to be consistent with being able to create JAR's using UNIX filename format or WIN32 filename format.