1 files changed, 34 insertions, 23 deletions
diff --git a/make/config/nativewindow/jawt-CustomJavaCode.java b/make/config/nativewindow/jawt-CustomJavaCode.java
index 3223a74b1..d3dc3845f 100644
--- a/make/config/nativewindow/jawt-CustomJavaCode.java
+++ b/make/config/nativewindow/jawt-CustomJavaCode.java
@@ -1,27 +1,38 @@
-private static volatile JAWT jawt;
+/** Available and recommended on Mac OS X >= 10.6 Update 4 */
+public static final int JAWT_MACOSX_USE_CALAYER = 0x80000000;
+public static final VersionNumber JAWT_MacOSXCALayerMinVersion = new VersionNumber(10,6,4);
+
+private int jawt_version_cached = 0;
+
+public final int getCachedVersion() {
+    return jawt_version_cached;
+}
 
 /** Helper routine for all users to call to access the JAWT. */
-public static JAWT getJAWT() {
-  if (jawt == null) {
-    synchronized (JAWT.class) {
-      if (jawt == null) {
-        JAWTUtil.initSingleton();
-        // Workaround for 4845371.
-        // Make sure the first reference to the JNI GetDirectBufferAddress is done
-        // from a privileged context so the VM's internal class lookups will succeed.
-        AccessController.doPrivileged(new PrivilegedAction() {
-            public Object run() {
-              JAWT j = JAWT.create();
-              j.setVersion(JAWTFactory.JAWT_VERSION_1_4);
-              if (!JAWTFactory.JAWT_GetAWT(j)) {
-                throw new RuntimeException("Unable to initialize JAWT");
+public static JAWT getJAWT(final int jawt_version_flags) {
+    JAWTUtil.initSingleton();
+    // Workaround for 4845371.
+    // Make sure the first reference to the JNI GetDirectBufferAddress is done
+    // from a privileged context so the VM's internal class lookups will succeed.
+    return AccessController.doPrivileged(new PrivilegedAction<JAWT>() {
+        public JAWT run() {
+          int jawt_version_flags_mod = jawt_version_flags;
+          JAWT jawt = JAWT.create();
+          if( 0 != ( jawt_version_flags_mod & JAWT_MACOSX_USE_CALAYER ) ) {
+              jawt.setVersion(jawt_version_flags_mod);
+              if (JAWTFactory.JAWT_GetAWT(jawt)) {
+                  jawt.jawt_version_cached = jawt.getVersion();
+                  return jawt;
               }
-              jawt = j;
-              return null;
-            }
-          });
-      }
-    }
-  }
-  return jawt;
+              jawt_version_flags_mod &= ~JAWT_MACOSX_USE_CALAYER;
+              System.err.println("MacOSX "+Platform.OS_VERSION_NUMBER+" >= "+JAWT_MacOSXCALayerMinVersion+": Failed to use JAWT_MACOSX_USE_CALAYER");
+          }
+          jawt.setVersion(jawt_version_flags_mod);
+          if (!JAWTFactory.JAWT_GetAWT(jawt)) {
+            throw new RuntimeException("Unable to initialize JAWT: 0x"+Integer.toHexString(jawt_version_flags_mod));
+          }
+          jawt.jawt_version_cached = jawt.getVersion();
+          return jawt;
+        }
+      });
 }