Icon Handling throw a NullPointerException

Question

I have added a image for my Jlist element, but when i run that frame this exception will be thrown:

java.lang.NullPointerException
at javax.swing.ImageIcon.<init>(ImageIcon.java:217)
at org.openstreetmap.josm.plugins.laneconnector.LaneRelationsDialog.createImageMap(LaneRelationsDialog.java:527)
at org.openstreetmap.josm.plugins.laneconnector.LaneRelationsDialog.<init>(LaneRelationsDialog.java:363)
at org.openstreetmap.josm.plugins.laneconnector.LaneRelationsAction.actionPerformed(LaneRelationsAction.java:38)
at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1663)
at javax.swing.JComponent.processKeyBinding(JComponent.java:2879)
at javax.swing.KeyboardManager.fireBinding(KeyboardManager.java:307)
at javax.swing.KeyboardManager.fireKeyboardAction(KeyboardManager.java:263)
at javax.swing.JComponent.processKeyBindingsForAllComponents(JComponent.java:2971)
at javax.swing.JComponent.processKeyBindings(JComponent.java:2963)
at javax.swing.JComponent.processKeyEvent(JComponent.java:2842)
at java.awt.Component.processEvent(Component.java:6304)
at java.awt.Container.processEvent(Container.java:2234)
at java.awt.Component.dispatchEventImpl(Component.java:4883)
at java.awt.Container.dispatchEventImpl(Container.java:2292)
at java.awt.Component.dispatchEvent(Component.java:4705)
at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954)
at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:806)
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1074)
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:945)
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:771)
at java.awt.Component.dispatchEventImpl(Component.java:4754)
at java.awt.Container.dispatchEventImpl(Container.java:2292)
at java.awt.Window.dispatchEventImpl(Window.java:2739)
at java.awt.Component.dispatchEvent(Component.java:4705)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:746)
at java.awt.EventQueue.access$400(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:697)
at java.awt.EventQueue$3.run(EventQueue.java:691)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.awt.EventQueue$4.run(EventQueue.java:719)
at java.awt.EventQueue$4.run(EventQueue.java:717)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:716)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

line 217:

     public ImageIcon(URL location){
     this(location, location.toExternalForm());}

line 527:

 map.put(s, new ImageIcon(getClass().getResource("/images/right.png")));

I checked System.out.println(getClass().getResource("/images/right.png")); and returns null. Also, i copied this picture in bin folder, but error is the same. why? Please help me!

Answer 1

getResource() Finds a resource with a given name. The rules for searching resources associated with a given class are implemented by the defining class loader of the class.

Make sure that your file present in class path or in project.