Hi!

My code worked correctly, but now it produces the error message. It seems that the command treeModel.reload(); doesn't work anymore.

Please explain me what happens?

private void addOrgFolder() {
         String[] data = new String[2];
         data[0] = text2.getText(); data[1] = text1.getText();
         DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode)SystClasses.TreeEditTest.tree1.getLastSelectedPathComponent();
         tableModel.setQueryDontChangeTable("insert ...");

         DefaultMutableTreeNode nNode = new DefaultMutableTreeNode(data[1]);    
         treeModel = (DefaultTreeModel)SystClasses.TreeEditTest.tree1.getModel();
         treeModel.reload();
         treeModel.insertNodeInto(nNode, selectedNode, selectedNode.getChildCount());
}
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at SystClasses.TreeEditTest$2.valueChanged(TreeEditTest.java:153)
        at javax.swing.JTree.fireValueChanged(JTree.java:2820)
        at javax.swing.JTree$TreeSelectionRedirector.valueChanged(JTree.java:3191)
        at javax.swing.tree.DefaultTreeSelectionModel.fireValueChanged(DefaultTreeSelectionModel.java:629)
        at javax.swing.tree.DefaultTreeSelectionModel.clearSelection(DefaultTreeSelectionModel.java:570)
        at javax.swing.tree.VariableHeightLayoutCache.rebuild(VariableHeightLayoutCache.java:740)
        at javax.swing.tree.VariableHeightLayoutCache.treeStructureChanged(VariableHeightLayoutCache.java:626)
        at javax.swing.plaf.basic.BasicTreeUI$Handler.treeStructureChanged(BasicTreeUI.java:3824)
        at javax.swing.tree.DefaultTreeModel.fireTreeStructureChanged(DefaultTreeModel.java:561)
        at javax.swing.tree.DefaultTreeModel.reload(DefaultTreeModel.java:279)
        at javax.swing.tree.DefaultTreeModel.reload(DefaultTreeModel.java:194)
        at SystClasses.Folder.addOrgFolder(Folder.java:261)
        at SystClasses.Folder.access$700(Folder.java:39)
        at SystClasses.Folder$2.actionPerformed(Folder.java:99)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
        at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
        at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:272)
        at java.awt.Component.processMouseEvent(Component.java:6263)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
        at java.awt.Component.processEvent(Component.java:6028)
        at java.awt.Container.processEvent(Container.java:2041)
        at java.awt.Component.dispatchEventImpl(Component.java:4630)
        at java.awt.Container.dispatchEventImpl(Container.java:2099)
        at java.awt.Component.dispatchEvent(Component.java:4460)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4574)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
        at java.awt.Container.dispatchEventImpl(Container.java:2085)
        at java.awt.Window.dispatchEventImpl(Window.java:2478)
        at java.awt.Component.dispatchEvent(Component.java:4460)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

On the line 153 I have:

tree1.addTreeSelectionListener(new TreeSelectionListener() {
            public void valueChanged(TreeSelectionEvent e) {
...
folderType = returnDataFromSelectQuery("select ..."); // Line 153
...
}

Well, I changed the sequence of some commands:

DefaultMutableTreeNode nNode = new DefaultMutableTreeNode(data[1]);    
         treeModel = (DefaultTreeModel)SystClasses.TreeEditTest.tree1.getModel();
         treeModel.insertNodeInto(nNode, selectedNode, selectedNode.getChildCount());

         addFolderToFTPServer(selectedNode, data[1]);

         treeModel.reload();

Now, I can see a new node added to the tree. But still treeModel.reload() produces the same error.

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