RFR: 8247995: Avoid use of a mapping function in Permissions.getPermissionCollection

[Roger Riggs]

Hi Claes,

Its correct as is but I would have written it without duplicating the 
'permsMap.get(p.getClass())' invocation
and as a single method (unless the inlining of 
getPermissionCollection(p,create)) is important.

A patch on top of yours:

diff --git a/src/java.base/share/classes/java/security/Permissions.java 
b/src/java.base/share/classes/java/security/Permissions.java
--- a/src/java.base/share/classes/java/security/Permissions.java
+++ b/src/java.base/share/classes/java/security/Permissions.java
@@ -229,20 +229,16 @@ implements Serializable
       */
      private PermissionCollection getPermissionCollection(Permission p,
boolean createEmpty) {
+        PermissionCollection pc = permsMap.get(p.getClass());
          if (!hasUnresolved && !createEmpty) {
              // Collection not to be created
-            return permsMap.get(p.getClass());
+            return pc;
          }
-        PermissionCollection pc = permsMap.get(p.getClass());
          if (pc != null) {
              // Collection already created
              return pc;
          }
-        return createPermissionCollection(p, createEmpty);
-    }

-    private PermissionCollection createPermissionCollection(Permission p,
- boolean createEmpty) {
          synchronized (permsMap) {
              Class<?> c = p.getClass();
              PermissionCollection pc = permsMap.get(c);

Thanks, Roger


On 6/22/20 11:04 AM, Claes Redestad wrote:
> Hi,
>
> this patch fixes a corner-case performance issue with
> Permissions.implies(Permission) by not needing to allocate a mapper
> function (or lambda) on each invocation of getPermissionCollection
> when there are unresolved permissions present.
>
> Bug:   https://bugs.openjdk.java.net/browse/JDK-8247995
> Patch: http://cr.openjdk.java.net/~redestad/8247995/open.00/
>
> Testing: tier1-2
>
> Thanks!
>
> /Claes