Private and final modifiers added to class attribute

GUI/src/main/java/cz/fidentis/analyst/core/ControlPanelBuilder.java

@@ -558,7 +558,7 @@ public class ControlPanelBuilder {
         }
 
         minusButton.addActionListener(new AbstractAction() {
-            double minimum = range == null ? PERCENTAGE_VALUE_MINIMUM : range.getMinimum();
+            private final double minimum = range == null ? PERCENTAGE_VALUE_MINIMUM : range.getMinimum();
             
             @Override
             public void actionPerformed(ActionEvent ae) {
@@ -577,7 +577,7 @@ public class ControlPanelBuilder {
             }
         });
         plusButton.addActionListener(new AbstractAction() {
-            double maximum = range == null ? PERCENTAGE_VALUE_MAXIMUM : range.getMaximum();
+            private final double maximum = range == null ? PERCENTAGE_VALUE_MAXIMUM : range.getMaximum();
             
             @Override
             public void actionPerformed(ActionEvent ae) {