NPE При запуске NetBeans с использованием GTK LAF

Question

NPE При запуске NetBeans с использованием GTK LAF

Недавно я получил странный след стека в логах netbeans (я добавил его в конец этого поста). Я был в состоянии отследить это до LAF. Эта ошибка возникает при запуске Netbeans с использованием GTK LAF, но отлично работает в Metal и с использованием собственного Windows LAF.

Кажется, что экземпляр PropertyChangeSupport имеет значение NULL, поэтому он добавляет ошибку при добавлении прослушивателя изменения свойства. Вот сокращенный источник моего пользовательского компонента:

public class EnterprisePicker extends javax.swing.JPanel implements ActionListener, KeyListener, ListSelectionListener, UnitContainer {

    private static final Logger logger = IdeUiUtil.initLogger(EnterprisePicker.class.getName());
    protected InfoPanelStyle infoPanelStyle = InfoPanelStyle.FULL;
    private final PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);
    public static final String PROP_INFOPANELSTYLE = "infoPanelStyle";

    /** Creates the new component */
    public EnterprisePicker() {
        // [... snip ...]
    }

    // [ ... snip ... ]

    /**
     * Add PropertyChangeListener.
     *
     * @param listener
     */
    @Override
    public void addPropertyChangeListener(PropertyChangeListener listener) {
        propertyChangeSupport.addPropertyChangeListener(listener);
    }

    // [ ... snip ... ]

}

Очевидно, я мог бы просто защитить эти звонки, используя if (propertyChangeSupport == null)... Но не нарушит ли это свойства позже в приложении? Предполагая, что ни один слушатель никогда не будет подключен, так как экземпляр null...?

Трассировки стека

INFO [org.netbeans.modules.form.BeanSupport]: Cannot create default instance of: org.statec.ide.ui.components.EnterprisePicker
java.lang.NullPointerException
        at org.statec.ide.ui.components.EnterprisePicker.addPropertyChangeListener(EnterprisePicker.java:654)
        at javax.swing.plaf.synth.SynthPanelUI.installListeners(SynthPanelUI.java:49)
        at javax.swing.plaf.synth.SynthPanelUI.installUI(SynthPanelUI.java:38)
        at javax.swing.JComponent.setUI(JComponent.java:662)
        at javax.swing.JPanel.setUI(JPanel.java:136)
        at javax.swing.JPanel.updateUI(JPanel.java:109)
        at javax.swing.JPanel.<init>(JPanel.java:69)
        at javax.swing.JPanel.<init>(JPanel.java:92)
        at javax.swing.JPanel.<init>(JPanel.java:100)
        at org.statec.ide.ui.components.EnterprisePicker.<init>(EnterprisePicker.java:39)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)
        at org.netbeans.modules.form.CreationFactory.createDefaultInstance(CreationFactory.java:168)
[catch] at org.netbeans.modules.form.BeanSupport.createBeanInstance(BeanSupport.java:83)
        at org.netbeans.modules.form.BeanSupport.getDefaultInstance(BeanSupport.java:109)
        at org.netbeans.modules.form.GandalfPersistenceManager.restoreComponent(GandalfPersistenceManager.java:769)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadComponent(GandalfPersistenceManager.java:1007)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadForm(GandalfPersistenceManager.java:527)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadForm(GandalfPersistenceManager.java:299)
        at org.netbeans.modules.form.FormEditor$3.run(FormEditor.java:337)
        at org.netbeans.modules.form.FormLAF$2.run(FormLAF.java:293)
        at org.openide.util.Mutex.doEventAccess(Mutex.java:1361)
        at org.openide.util.Mutex.readAccess(Mutex.java:320)
        at org.netbeans.modules.form.FormLAF.executeWithLookAndFeel(FormLAF.java:276)
        at org.netbeans.modules.form.FormEditor.loadFormData(FormEditor.java:334)
        at org.netbeans.modules.form.FormEditor.loadFormDesigner(FormEditor.java:232)
        at org.netbeans.modules.form.FormDesigner.finishComponentShowing(FormDesigner.java:1932)
        at org.netbeans.modules.form.FormDesigner.access$1100(FormDesigner.java:107)
        at org.netbeans.modules.form.FormDesigner$PreLoadTask$1.run(FormDesigner.java:1897)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
        at java.awt.EventQueue.access$000(EventQueue.java:84)
        at java.awt.EventQueue$1.run(EventQueue.java:602)
        at java.awt.EventQueue$1.run(EventQueue.java:600)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:148)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
INFO
org.openide.ErrorManager$AnnException: msg
        at org.openide.ErrorManager$AnnException.findOrCreate(ErrorManager.java:866)
        at org.openide.ErrorManager$DelegatingErrorManager.annotate(ErrorManager.java:653)
        at org.netbeans.modules.form.GandalfPersistenceManager.annotateException(GandalfPersistenceManager.java:237)
        at org.netbeans.modules.form.GandalfPersistenceManager.annotateException(GandalfPersistenceManager.java:247)
        at org.netbeans.modules.form.GandalfPersistenceManager.restoreComponent(GandalfPersistenceManager.java:865)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadComponent(GandalfPersistenceManager.java:1007)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadForm(GandalfPersistenceManager.java:527)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadForm(GandalfPersistenceManager.java:299)
        at org.netbeans.modules.form.FormEditor$3.run(FormEditor.java:337)
        at org.netbeans.modules.form.FormLAF$2.run(FormLAF.java:293)
        at org.openide.util.Mutex.doEventAccess(Mutex.java:1361)
        at org.openide.util.Mutex.readAccess(Mutex.java:320)
        at org.netbeans.modules.form.FormLAF.executeWithLookAndFeel(FormLAF.java:276)
        at org.netbeans.modules.form.FormEditor.loadFormData(FormEditor.java:334)
        at org.netbeans.modules.form.FormEditor.loadFormDesigner(FormEditor.java:232)
        at org.netbeans.modules.form.FormDesigner.finishComponentShowing(FormDesigner.java:1932)
        at org.netbeans.modules.form.FormDesigner.access$1100(FormDesigner.java:107)
        at org.netbeans.modules.form.FormDesigner$PreLoadTask$1.run(FormDesigner.java:1897)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
        at java.awt.EventQueue.access$000(EventQueue.java:84)
        at java.awt.EventQueue$1.run(EventQueue.java:602)
        at java.awt.EventQueue$1.run(EventQueue.java:600)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:148)
        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)
msg
Caused: java.lang.NullPointerException
        at org.statec.ide.ui.components.EnterprisePicker.addPropertyChangeListener(EnterprisePicker.java:654)
        at javax.swing.plaf.synth.SynthPanelUI.installListeners(SynthPanelUI.java:49)
        at javax.swing.plaf.synth.SynthPanelUI.installUI(SynthPanelUI.java:38)
        at javax.swing.JComponent.setUI(JComponent.java:662)
        at javax.swing.JPanel.setUI(JPanel.java:136)
        at javax.swing.JPanel.updateUI(JPanel.java:109)
        at javax.swing.JPanel.<init>(JPanel.java:69)
        at javax.swing.JPanel.<init>(JPanel.java:92)
        at javax.swing.JPanel.<init>(JPanel.java:100)
        at org.statec.ide.ui.components.EnterprisePicker.<init>(EnterprisePicker.java:39)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)
        at org.netbeans.modules.form.CreationFactory.createDefaultInstance(CreationFactory.java:168)
        at org.netbeans.modules.form.RADComponent.createBeanInstance(RADComponent.java:252)
        at org.netbeans.modules.form.RADComponent.initInstance(RADComponent.java:191)
        at org.netbeans.modules.form.GandalfPersistenceManager.restoreComponent(GandalfPersistenceManager.java:851)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadComponent(GandalfPersistenceManager.java:1007)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadForm(GandalfPersistenceManager.java:527)
        at org.netbeans.modules.form.GandalfPersistenceManager.loadForm(GandalfPersistenceManager.java:299)
        at org.netbeans.modules.form.FormEditor$3.run(FormEditor.java:337)
        at org.netbeans.modules.form.FormLAF$2.run(FormLAF.java:293)
        at org.openide.util.Mutex.doEventAccess(Mutex.java:1361)
        at org.openide.util.Mutex.readAccess(Mutex.java:320)
        at org.netbeans.modules.form.FormLAF.executeWithLookAndFeel(FormLAF.java:276)
        at org.netbeans.modules.form.FormEditor.loadFormData(FormEditor.java:334)
[catch] at org.netbeans.modules.form.FormEditor.loadFormDesigner(FormEditor.java:232)
        at org.netbeans.modules.form.FormDesigner.finishComponentShowing(FormDesigner.java:1932)
        at org.netbeans.modules.form.FormDesigner.access$1100(FormDesigner.java:107)
        at org.netbeans.modules.form.FormDesigner$PreLoadTask$1.run(FormDesigner.java:1897)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
        at java.awt.EventQueue.access$000(EventQueue.java:84)
        at java.awt.EventQueue$1.run(EventQueue.java:602)
        at java.awt.EventQueue$1.run(EventQueue.java:600)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:148)
        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)
Error in loading component: [JDialog]->enterprisePicker1
Cannot create instance of org.statec.ide.ui.components.EnterprisePicker.
The component cannot be loaded.

И для справки:

malbert@dredg:~/.netbeans/7.0/var/log$ java -version
java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03)
Java HotSpot(TM) Server VM (build 20.1-b02, mixed mode)

malbert@dredg:~/.netbeans/7.0/var/log$ cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=11.04
DISTRIB_CODENAME=natty
DISTRIB_DESCRIPTION="Ubuntu 11.04"

1

java properties gtk look-and-feel

Источник

user160665 26 сен '11 в 13:06

1 ответ

Решение

Другие вопросы по тегам java properties gtk look-and-feel

user637853 26 сен '11 в 13:17 2011-09-26 13:17 · Accepted Answer · 2011-09-26 13:17

Просто предположение, но проблема может заключаться в том, что во время инициализации некоторого суперкласса addPropertyChangeListener(...) называется (javax.swing.JPanel.<init> может быть виновником), таким образом, этот вызов происходит раньше propertyChangeSupport инициализируется.

Последовательность инициализации полей экземпляра будет такой:

объект
Составная часть
Контейнер
JComponent
JPanel
EnterprisePicker

Если во время инициализации JPanel addPropertyChangeListener(...) метод вызывается, это будет фактически переопределенная версия EnterprisePicker, но EnterprisePickerполя еще не были бы инициализированы.

Чтобы исправить это, вы должны проверить null в этом методе и инициализировать при необходимости (или вызов super.addPropertyChangeListener(...), Есть ли необходимость иметь собственную реализацию (чтобы добавить свою PropertyChangeSupport)?