提交异常java.lang.UnsupportedClassVersionError: Bad version number in .class file

http://blog.csdn.net/myjava_024/feed.aspx解决了我郁闷了两个小时的问题

eclipse开发struts登陆界面报错提交用户名和密码时出现以下报错信息


HTTP Status 500 -

--------------------------------------------------------------------------------

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Servlet execution threw an exception


root cause

java.lang.UnsupportedClassVersionError: Bad version number in .class file
java.lang.ClassLoader.defineClass1(Native Method)
java.lang.ClassLoader.defineClass(ClassLoader.java:604)
java.security.SecureClassLoader.defineClass(SecureClassLoader.java:123)
org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1876)
org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:889)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1353)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1232)
org.apache.struts.util.RequestUtils.applicationClass(RequestUtils.java:117)
org.apache.struts.util.RequestUtils.applicationInstance(RequestUtils.java:143)
org.apache.struts.action.RequestProcessor.processActionCreate(RequestProcessor.java:292)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:230)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)


note The full stack trace of the root cause is available in the Apache Tomcat/5.5.27 logs.


--------------------------------------------------------------------------------

Apache Tomcat/5.5.27
解决办法：打开Eclipse》window》preferences》java》找到compiler并点击

               在右面的页面中找到compiler compliance level    改为5.0嗯

说明：这种问题很常见，好多人都知道嗯只是对新手来说，要花费不少时间！！