Bug 747: Allow usage of IdentityHashMap w/ keys: AbstractGraphicsDevice.getUniqueID() and GLContext.getDeviceVersionAvailableKey()

.. both value classes unique, long lived and rare.

2 files changed, 15 insertions, 4 deletions

diff --git a/src/nativewindow/classes/javax/media/nativewindow/AbstractGraphicsDevice.java b/src/nativewindow/classes/javax/media/nativewindow/AbstractGraphicsDevice.java
index 585cd1f09..ed305d49e 100644
--- a/src/nativewindow/classes/javax/media/nativewindow/AbstractGraphicsDevice.java
+++ b/src/nativewindow/classes/javax/media/nativewindow/AbstractGraphicsDevice.java
@@ -89,10 +89,16 @@ public interface AbstractGraphicsDevice extends Cloneable {
     public int getUnitID();
 
     /**
-     * Returns a unique ID String of this device using {@link #getType() type},
-     * {@link #getConnection() connection} and {@link #getUnitID() unitID}.<br>
-     * The unique ID does not reflect the instance of the device, hence the handle is not included.<br>
+     * Returns a unique ID object of this device using {@link #getType() type},
+     * {@link #getConnection() connection} and {@link #getUnitID() unitID} as it's key components.
+     * <p>
+     * The unique ID does not reflect the instance of the device, hence the handle is not included.
      * The unique ID may be used as a key for semantic device mapping.
+     * </p>
+     * <p>
+     * The returned string object reference is unique using {@link String#intern()}  
+     * and hence can be used as a key itself.
+     * </p>
      */
     public String getUniqueID();
 
diff --git a/src/nativewindow/classes/javax/media/nativewindow/DefaultGraphicsDevice.java b/src/nativewindow/classes/javax/media/nativewindow/DefaultGraphicsDevice.java
index 66b81d7fa..0bf5c2937 100644
--- a/src/nativewindow/classes/javax/media/nativewindow/DefaultGraphicsDevice.java
+++ b/src/nativewindow/classes/javax/media/nativewindow/DefaultGraphicsDevice.java
@@ -253,7 +253,12 @@ public class DefaultGraphicsDevice implements Cloneable, AbstractGraphicsDevice
          return toolkitLock;
     }
 
+   /** 
+    * Returns a unique String object using {@link String#intern()} for the given arguments, 
+    * which object reference itself can be used as a key.
+    */
     protected static String getUniqueID(String type, String connection, int unitID) {
-      return (type + separator + connection + separator + unitID).intern();
+      final String r = (type + separator + connection + separator + unitID).intern();
+      return r.intern();
     }
 }