potential null pointer fix

diff --git a/src/jalview/gui/ScalePanel.java b/src/jalview/gui/ScalePanel.java
index 045471a..33131d3 100755 (executable)
--- a/src/jalview/gui/ScalePanel.java
+++ b/src/jalview/gui/ScalePanel.java
@@ -64,7 +64,7 @@ public class ScalePanel extends JPanel implements MouseMotionListener,
    * DOCUMENT ME!
    * 
    * @param evt
-   *                DOCUMENT ME!
+   *          DOCUMENT ME!
    */
   public void mousePressed(MouseEvent evt)
   {
@@ -194,7 +194,7 @@ public class ScalePanel extends JPanel implements MouseMotionListener,
    * DOCUMENT ME!
    * 
    * @param evt
-   *                DOCUMENT ME!
+   *          DOCUMENT ME!
    */
   public void mouseReleased(MouseEvent evt)
   {
@@ -241,7 +241,7 @@ public class ScalePanel extends JPanel implements MouseMotionListener,
    * DOCUMENT ME!
    * 
    * @param evt
-   *                DOCUMENT ME!
+   *          DOCUMENT ME!
    */
   public void mouseDragged(MouseEvent evt)
   {
@@ -372,7 +372,7 @@ public class ScalePanel extends JPanel implements MouseMotionListener,
    * DOCUMENT ME!
    * 
    * @param g
-   *                DOCUMENT ME!
+   *          DOCUMENT ME!
    */
   public void paintComponent(Graphics g)
   {
@@ -399,23 +399,25 @@ public class ScalePanel extends JPanel implements MouseMotionListener,
 
     // Fill the selected columns
     ColumnSelection cs = av.getColumnSelection();
-    gg.setColor(new Color(220, 0, 0));
-
-    for (int i = 0; i < cs.size(); i++)
+    if (cs != null)
     {
-      int sel = cs.columnAt(i);
-      if (av.hasHiddenColumns)
-      {
-        sel = av.getColumnSelection().findColumnPosition(sel);
-      }
+      gg.setColor(new Color(220, 0, 0));
 
-      if ((sel >= startx) && (sel <= endx))
+      for (int i = 0; i < cs.size(); i++)
       {
-        gg.fillRect((sel - startx) * av.charWidth, 0, av.charWidth,
-                getHeight());
+        int sel = cs.columnAt(i);
+        if (av.hasHiddenColumns)
+        {
+          sel = cs.findColumnPosition(sel);
+        }
+
+        if ((sel >= startx) && (sel <= endx))
+        {
+          gg.fillRect((sel - startx) * av.charWidth, 0, av.charWidth,
+                  getHeight());
+        }
       }
     }
-
     // Draw the scale numbers
     gg.setColor(Color.black);