From Weijun Wang via jtreg-dev:

For every test with a policy file, jtreg creates a new one with some extra entries. On Windows, one of them is

grant {
    permission java.io.FilePermission "C:\tmp\W\classes${/}-", "read";
};

(Here, I provide -w:C:/tmp/W on the jtreg command line.)

The syntax of the file name is incorrect, it should be either "C:/tmp/..." or "C:\\tmp\\...". In fact, if I add -Djava.security.debug=policy to jtreg, I will see

   policy: granting ("java.io.FilePermission" "C: mpWclasses\-" "read")

This seems to be harmless now, but in our experiment of implementing FilePermission with NIO Path, the path will be rejected because it contains the illegal char \t.

I have a patch here.

diff --git a/src/share/classes/com/sun/javatest/regtest/Action.java b/src/share/classes/com/sun/javatest/regtest/Action.java
--- a/src/share/classes/com/sun/javatest/regtest/Action.java
+++ b/src/share/classes/com/sun/javatest/regtest/Action.java
@@ -182,7 +182,7 @@
                 fw.write("// The following grant entries were added by JavaTest. Do not edit." + LINESEP);
                 fw.write("grant {" + LINESEP);
                 fw.write(" permission java.io.FilePermission \""
- + script.absTestClsTopDir().getPath().replace('\\' + FILESEP, "{/}")
+ + script.absTestClsTopDir().getPath().replace(FILESEP, "${/}")
                         + "${/}-\"" + ", \"read\";" + LINESEP);
                 fw.write("};" + LINESEP);
                 for (File f: script.getJavaTestClassPath().split()) {

I have no idea why the old code substitutes \\ to {/}. I've changed it to \ to ${/}.

Thanks
Max