Multiple java.lang.IllegalArgumentException: Child tree not found. exceptions 
are thrown in file which is incorrectly formatted. Stack trace:
java.lang.IllegalArgumentException: Child tree not found.
	at org.netbeans.modules.javacore.parser.ASTProvider.findTree(ASTProvider.
java:262)
	at org.netbeans.modules.javacore.parser.ElementInfo.
refreshASTree(ElementInfo.java:80)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.MetadataElement.
getASTree(MetadataElement.java:998)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.MetadataElement.
getASTree(MetadataElement.java:509)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.MetadataElement.
getPosition(MetadataElement.java:515)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.FeatureImpl.
getPosition(FeatureImpl.java:280)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.ElementFinder.
getElementByOffset(ElementFinder.java:37)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.ResourceImpl.
getElementByOffset(ResourceImpl.java:1640)
	at org.netbeans.modules.java.hints.JavaHintsProvider.
getHints(JavaHintsProvider.java:121)
	at org.netbeans.modules.editor.hints.HintsOperator$HintPopupTaskImpl.
run(HintsOperator.java:233)
	at org.openide.util.Task.run(Task.java:207)
	at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:469)
[catch] at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.
java:870)

Java file which cause this exception is here:
/*
 * HelloMidlet.java
 *
 * Created on 04 November 2005, 15:04
 */

package hello;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

/**
 *
 * @author lukas
 */
public class HelloMidlet extends MIDlet implements javax.microedition.lcdui.
CommandListener
{
    
    /** Creates a new instance of HelloMidlet */
    public HelloMidlet()
    {
        initialize();
    }
    
    private javax.microedition.lcdui.Form helloForm;//GEN-BEGIN:MVDFields
    private javax.microedition.lcdui.StringItem helloStringItem;
    private javax.microedition.lcdui.Command exitCommand;//GEN-END:MVDFields
    
    /** This method initializes UI of the application.//GEN-BEGIN:MVDMethods
     */
    private void initialize()
    {
        getDisplay().setCurrent(get_helloForm());
    }//GEN-END:MVDMethods
    
    /** Called by the system to indicate that a command has been invoked on a 
particular displayable.//GEN-BEGIN:MVDCABegin
     * @param command the Command that ws invoked
     * @param displayable the Displayable on which the command was invoked
     */
    public void commandAction(javax.microedition.lcdui.Command command, javax.
microedition.lcdui.Displayable displayable)
    {//GEN-END:MVDCABegin
    {
        // Insert global pre-action code here
        if (displayable == helloForm)//GEN-BEGIN:MVDCABody
        {
            if (command == exitCommand)
            {//GEN-END:MVDCABody
            {
                // Insert pre-action code here
                exitMIDlet();//GEN-LINE:MVDCAAction3
                // Insert post-action code here
            }//GEN-BEGIN:MVDCACase3
            }//GEN-END:MVDCACase3
        // Insert global post-action code here
    }//GEN-LINE:MVDCAEnd
    
    /**
     * This method should return an instance of the display.
     */
    public javax.microedition.lcdui.Display getDisplay () {//GEN-FIRST:
MVDGetDisplay
    {
        return javax.microedition.lcdui.Display.getDisplay(this);
    }//GEN-LAST:MVDGetDisplay
    
    /**
     * This method should exit the midlet.
     */
    public void exitMIDlet () {//GEN-FIRST:MVDExitMidlet
    {
        getDisplay().setCurrent(null);
        destroyApp(true);
        notifyDestroyed();
    }//GEN-LAST:MVDExitMidlet
    
    /** This method returns instance for helloForm component and should be 
called instead of accessing helloForm field directly.//GEN-BEGIN:MVDGetBegin2
     * @return Instance for helloForm component
     */
    public javax.microedition.lcdui.Form get_helloForm()
    {
        if (helloForm == null)
        {//GEN-END:MVDGetBegin2
        {
            // Insert pre-init code here
            helloForm = new javax.microedition.lcdui.Form(null, new javax.
microedition.lcdui.Item[] {get_helloStringItem()});//GEN-BEGIN:MVDGetInit2
            helloForm.addCommand(get_exitCommand());
            helloForm.setCommandListener(this);//GEN-END:MVDGetInit2
            // Insert post-init code here
        }//GEN-BEGIN:MVDGetEnd2
        return helloForm;
        }//GEN-END:MVDGetEnd2
    
        /** This method returns instance for helloStringItem component and 
should be called instead of accessing helloStringItem field directly.//GEN-
BEGIN:MVDGetBegin4
         * @return Instance for helloStringItem component
         */
        public javax.microedition.lcdui.StringItem get_helloStringItem()
        {
            if (helloStringItem == null)
            {//GEN-END:MVDGetBegin4
        {
            // Insert pre-init code here
            helloStringItem = new javax.microedition.lcdui.StringItem("Hello", 
"Hello, World!");//GEN-LINE:MVDGetInit4
            // Insert post-init code here
        }//GEN-BEGIN:MVDGetEnd4
        return helloStringItem;
            }//GEN-END:MVDGetEnd4
    
            /** This method returns instance for exitCommand component and 
should be called instead of accessing exitCommand field directly.//GEN-BEGIN:
MVDGetBegin5
             * @return Instance for exitCommand component
             */
            public javax.microedition.lcdui.Command get_exitCommand()
            {
                if (exitCommand == null)
                {//GEN-END:MVDGetBegin5
        {
            // Insert pre-init code here
            exitCommand = new javax.microedition.lcdui.Command("Exit", javax.
microedition.lcdui.Command.EXIT, 1);//GEN-LINE:MVDGetInit5
            // Insert post-init code here
        }//GEN-BEGIN:MVDGetEnd5
        return exitCommand;
                }//GEN-END:MVDGetEnd5
    
    public void startApp()
    {
    }
    
    public void pauseApp()
    {
    }
    
    public void destroyApp(boolean unconditional)
    {
    }
    
}