[NO ISSUE] Fix ClassCastExceptions in MXHelper

Change-Id: Ibf79fe10447f0f7e93c421c9b10b6f4cb84a6a60
Reviewed-on: https://asterix-gerrit.ics.uci.edu/2669
Sonar-Qube: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Murtadha Hubail <mhubail@apache.org>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
diff --git a/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MXHelper.java b/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MXHelper.java
index 2b65106..ce20d37 100644
--- a/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MXHelper.java
+++ b/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MXHelper.java
@@ -64,24 +64,24 @@
         return getOpenFileDescriptorCount != null;
     }
 
-    public static Integer getCurrentOpenFileCount() {
+    public static long getCurrentOpenFileCount() {
         if (getOpenFileDescriptorCount == null) {
             return -1;
         }
         try {
-            return (Integer) getOpenFileDescriptorCount.invoke(osMXBean);
+            return (long) getOpenFileDescriptorCount.invoke(osMXBean);
         } catch (Throwable e) { // NOSONAR
             LOGGER.log(Level.WARN, "Failure invoking getOpenFileDescriptorCount", e);
             return -1;
         }
     }
 
-    public static Integer getMaxOpenFileCount() {
+    public static long getMaxOpenFileCount() {
         if (getMaxFileDescriptorCount == null) {
             return -1;
         }
         try {
-            return (Integer) getMaxFileDescriptorCount.invoke(osMXBean);
+            return (long) getMaxFileDescriptorCount.invoke(osMXBean);
         } catch (Throwable e) { // NOSONAR
             LOGGER.log(Level.WARN, "Failure invoking getMaxFileDescriptorCount", e);
             return -1;