我目前正在为OpenOffice开发扩展程序。我正在使用Java 1.6和OpenOffice SDK 4.1.2。
如果尝试创建javax.swing.JTextPane,则在JTextPane的构造函数中会收到NullpointerException。
public class Dialog extends javax.JFrame {
private final JTextPane jTextPane;
private final JTable jTable;
public Dialog() {
jTable = new JTable();
jTextPane = new JTextPane();
}
}
对话框在另一个线程中初始化:
public class DialogManager {
private static JournalDialog journalDialog;
public void showDialog() {
Thread startThread = new Thread(new Runnable() {
@Override
public void run() {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
dialog = new Dialog();
...
}
}
}
}
}}
JTable的创建工作正常,但是在下一行中,我得到了Nullpointerexception
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.util.Hashtable.put(Unknown Source)
at javax.swing.JEditorPane.registerEditorKitForContentType(Unknown Source)
at javax.swing.JEditorPane.registerEditorKitForContentType(Unknown Source)
at javax.swing.JEditorPane.loadDefaultKitsIfNecessary(Unknown Source)
at javax.swing.JEditorPane.getKitTypeRegistry(Unknown Source)
at javax.swing.JEditorPane.getEditorKitClassNameForContentType(Unknown Source)
at javax.swing.JTextPane.<init>(Unknown Source)
at .gui.Dialog.<init>(Dialog.java:159)
at .gui.DialogManager$6$1.run(DialogManager.java:334)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
我希望有人知道导致此异常的原因。我试图在Java 1.7和1.8中运行扩展,但是存在相同的问题。
最好的祝福
2016年8月16日更新:
如果我在Netbeans面板上将JTexPane添加到Designer中,则它将起作用。只有构造函数中的初始化失败。
最佳答案
在不崩溃的情况下,可能无法将Swing用于此任务。而是使用com.sun.star.awt模块。完整的示例位于http://api.libreoffice.org/examples/DevelopersGuide/examples.html#GraphicalUserInterfaces。
有关更多信息,请参见Creating Dialogs at Runtime。
还有一个链接:This example确实使用了Swing。尝试看看是否发生相同的问题。