Question

我们有一个应用程序，它从登录页面开始，然后导航到加载小程序的第二个页面。一切都很好。当用户注销时，浏览器将导航回登录屏幕。如果用户再次登录，则初始化applet的某些部分时浏览器会崩溃。这只发生在第二次加载applet时。浏览器中已禁用缓存，但浏览器永远不会完全关闭，所以我认为第一次登录时加载的applet仍然存在吗？

更多信息。 applet加载时会出现sun java控制台。当用户注销并返回登录屏幕时，即使登录屏幕不使用java（仅限html和javascript），sun java控制台仍然处于启动状态。我认为当用户注销但是小程序被停止并被销毁时，某些东西没有被重新初始化，所以还有什么可能仍然存在？奇怪的是，这只发生在一台试验机上，而不发生在其他试验机上。

以下是SJC的错误日志：

java.lang.NullPointerException
    at javax.swing.text.html.parser.Parser.errorContext(Unknown Source)
    at javax.swing.text.html.parser.Parser.parse(Unknown Source)
    at javax.swing.text.html.parser.DocumentParser.parse(Unknown Source)
    at javax.swing.text.html.parser.ParserDelegator.parse(Unknown Source)
    at javax.swing.text.html.HTMLEditorKit.read(Unknown Source)
    at javax.swing.JEditorPane.setText(Unknown Source)
    at ReportPane.setDescription(ReportPane.java:577)
    at ReportPane.doDefineLoad(ReportPane.java:608)
    at ReportPane.<init>(ReportPane.java:565)
    at RevApp2.createGui(RevApp2.java:640)
    at RevApp2.access$0(RevApp2.java:414)
    at RevApp2$1.run(RevApp2.java:393)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)
asDescription-><font face="CENTURY SCHOOLBOOK">Use to assign accounts to coders.</font>
java.lang.reflect.InvocationTargetException
    at java.awt.EventQueue.invokeAndWait(Unknown Source)
    at javax.swing.SwingUtilities.invokeAndWait(Unknown Source)
    at RevApp2.init(RevApp2.java:389)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
    at javax.swing.text.html.parser.Parser.errorContext(Unknown Source)
    at javax.swing.text.html.parser.Parser.parse(Unknown Source)
    at javax.swing.text.html.parser.DocumentParser.parse(Unknown Source)
    at javax.swing.text.html.parser.ParserDelegator.parse(Unknown Source)
    at javax.swing.text.html.HTMLEditorKit.read(Unknown Source)
    at javax.swing.JEditorPane.setText(Unknown Source)
    at AdminPane.setDescription(AdminPane.java:197)
    at AdminPane.<init>(AdminPane.java:174)
    at RevApp2.createGui(RevApp2.java:656)
    at RevApp2.access$0(RevApp2.java:414)
    at RevApp2$1.run(RevApp2.java:393)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)
netscape.javascript.JSException: Unspecified error invoking method or accessing property "accountfocus"
    at sun.plugin2.main.client.MessagePassingJSObject.newJSException(Unknown Source)
    at sun.plugin2.main.client.MessagePassingJSObject.waitForReply(Unknown Source)
    at sun.plugin2.main.client.MessagePassingJSObject.call(Unknown Source)
    at RevApp2.start(RevApp2.java:2045)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Exception: netscape.javascript.JSException: Unspecified error invoking method or accessing property "accountfocus"

Answer 1

如果你谷歌“javax.swing.text.html.parser.Parser.errorContext”你会发现其他人有类似的问题并在一些oracle讨论板上报告过：

http://forums.oracle.com/forums/thread.jspa?messageID=8297744&tstart=0

他们谈论了一个解决方法 - 也许这也适合你的情况。

来自论坛的Qute：

我不明白是不是   正确的运行，但能够逃避   当我这样做的时候。

JEditorPane htmlPane = new   JEditorPane（“text / html”，html）;

Answer 2

解决此问题的方法如下：

  editorPane.setEditorKit(new HTMLEditorKit() {
   protected Parser getParser() {
    try {
     Class c = Class
       .forName("javax.swing.text.html.parser.ParserDelegator");
     Parser defaultParser = (Parser) c.newInstance();
     return defaultParser;
    } catch (Throwable e) {
    }
    return null;
   }
  });

第二次启动时Applet崩溃 - 提供错误日志

2 个答案: