Applet错误
我编写了一个Applet  在单击Applet上一按钮，java控制台出现错误：
java.lang.ExceptionInInitializerError thrown while loading gnu.io.RXTXCommDriver
Exception in thread "AWT-EventQueue-2" java.lang.ExceptionInInitializerError
at shujucaiji.Jiankong_Applet.actionPerformed(Jiankong_Applet.java:304)
at java.awt.Button.processActionEvent(Unknown Source)
at java.awt.Button.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(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.security.AccessControlException: access denied (java.lang.RuntimePermission loadLibrary.rxtxSerial)
at java.security.AccessControlContext.checkPermission(Unknown Source)
at java.security.AccessController.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkLink(Unknown Source)
at java.lang.Runtime.loadLibrary0(Unknown Source)
at java.lang.System.loadLibrary(Unknown Source)
at gnu.io.CommPortIdentifier.<clinit>(CommPortIdentifier.java:83)
... 12 more
这是错误怎么解决  是不是要生成Applet签名证书
------解决方案--------------------
在你的%JAVA_HOME%/jre\lib\security/java.policy里面追加
permission java.util.RuntimePermission "loadLibrary", "";
不然不允许你访问本地的jar包。