登陆连接的适合发生错误，提示如下： 严重: Allocate exception for servlet LoginServlet java.lang.UnsupportedClassVersionError: Bad version number in .class file at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(Unknown Source) at java.security.SecureClassLoader.defineClass(Unknown Source) at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1629) at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:850) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1299) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1181) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1027) at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:750) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:130) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527) at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684) at java.lang.Thread.run(Unknown Source)
