Question

我有一个关于在google app引擎上使用java applet的问题。我创建了两个名为InteractiveGraphView1和SimpleApplet的类。在SimpleApplet中使用InteractiveGraphView1的对象。无论如何，我正在为这两个类使用一些外部罐子。我为我的项目创建了一个名为“GraphApplet”的jar。然后我将这个jar放入WEB-INF / lib中，并将其作为外部jar添加到gae项目中。为了确保我还将我在GraphApplet类中使用的外部jar添加到我的gae项目中。我部署了gae项目，当我尝试运行applet时，它给了我这个错误：

load: class SimpleApplet.class not found.
java.lang.ClassNotFoundException: SimpleApplet.class
at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Unknown Source)
at sun.plugin2.applet.Plugin2Manager.createApplet(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception: java.lang.ClassNotFoundException: SimpleApplet.class
java.lang.RuntimeException: java.lang.NoClassDefFoundError:    edu/uci/ics/jung/algorithms/layout/Layout
at sun.plugin2.applet.Plugin2Manager.createApplet(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoClassDefFoundError: edu/uci/ics/jung/algorithms/layout/Layout
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Unknown Source)
at java.lang.Class.getConstructor0(Unknown Source)
at java.lang.Class.newInstance0(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$12.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$400(Unknown Source)
at java.awt.EventQueue$2.run(Unknown Source)
at java.awt.EventQueue$2.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.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)
  Caused by: java.lang.ClassNotFoundException: edu.uci.ics.jung.algorithms.layout.Layout
at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 20 more
Exception: java.lang.RuntimeException: java.lang.NoClassDefFoundError: edu/uci/ics/jung/algorithms/layout/Layout

我该怎么办？

P.S。我忘了告诉我在GraphApplet项目中使用JUNG库。我还将其添加到谷歌应用引擎项目

添加到HMTL

<html>

Hello App Engine

This is my page<br>
Below you see an applet<br>
<br>
<Applet Code="SimpleApplet.java" archive="graphic.jar" width=200 Height=200>
</Applet>

Answer 1

Applet只是一个jar文件，由浏览器下载并在客户端作为applet执行。

它与服务器代码无关。从服务器的角度来看，它只是一个静态文件。所以你不应该在服务器库驻留的WEB-INF/lib内部进行pout。把它放在你的html文件旁边。

对于引用其他jar的applet，请参阅：How do I build an applet which needs an external jar, using ant?

Answer 2

将您的applet.jar放到WAR目录的根目录

在谷歌应用程序引擎项目中使用Java小程序

2 个答案: