Question

就像标题所说：为什么我在浏览器中得到java.lang.reflect.InvocationTargetException而在eclipse applet viewer中却没有？当我在浏览器中使用html加载它来运行我的applet（是的，我知道applet已经过时）时，我得到了java.lang.reflect.InvocationTargetException错误。我读到当HTML试图加载不是applet的东西时会发生这种情况，但是当我在eclipse中将它作为applet运行时它会起作用（带来eclipse java applet viewer并且工作完美......这就是让我烦恼的事）。这是堆栈跟踪：

java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
    at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.runOnEDTAndWait(Unknown Source)
    at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.instantiateApplet(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager.initAppletAdapter(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
    at com.sun.deploy.uitoolkit.impl.awt.OldPluginAWTUtil.invokeAndWait(Unknown Source)
    ... 5 more
Caused by: java.security.AccessControlException: access denied ("java.io.FilePermission" "hq.gif" "read")
    at java.security.AccessControlContext.checkPermission(AccessControlContext.java:372)
    at java.security.AccessController.checkPermission(AccessController.java:559)
    at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
    at sun.plugin2.applet.AWTAppletSecurityManager.checkPermission(Unknown Source)
    at java.lang.SecurityManager.checkRead(SecurityManager.java:888)
    at sun.awt.SunToolkit.getImageFromHash(SunToolkit.java:774)
    at sun.awt.SunToolkit.getImage(SunToolkit.java:790)
    at sun.lwawt.macosx.LWCToolkit.getImage(LWCToolkit.java:471)
    at javax.swing.ImageIcon.<init>(ImageIcon.java:147)
    at javax.swing.ImageIcon.<init>(ImageIcon.java:174)
    at Application.Game.<init>(Game.java:97)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at java.lang.Class.newInstance(Class.java:374)
    at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter$1.run(Unknown Source)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:302)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:733)
    at java.awt.EventQueue.access$200(EventQueue.java:103)
    at java.awt.EventQueue$3.run(EventQueue.java:694)
    at java.awt.EventQueue$3.run(EventQueue.java:692)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
    at java.awt.EventQueue$4.run(EventQueue.java:708)
    at java.awt.EventQueue$4.run(EventQueue.java:706)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

我的文件结构是这样的：

index.html
java.policy.applet
hq.gif
b.gif
k.gif
Application (this is the package)/
     Game.java
     Game.class
     ETC

我的java.policy.applet

grant {
  permission java.security.AllPermission;
};

Answer 1

InvocationtargetException is a generic one. The actual exception is

引起：java.security.AccessControlException：访问被拒绝（＆＃34; java.io.FilePermission＆＃34;＆＃34; hq.gif＆＃34;＆＃34;阅读＆＃34;）

我认为，除了签名的jar之外，在运行applet时还需要管理员权限。

是否可以合并以下代码，如here

所述

AccessController.doPrivileged(new PrivilegedAction() {
    public Object run() {
        // perform the security-sensitive operation here
        return null;
    }
});

为什么我在浏览器中得到java.lang.reflect.InvocationTargetException但在eclipse applet viewer中没有？

1 个答案: