我的Servlet代码：
@WebServlet(description = "A simple", urlPatterns = { "/SimpleServlet" })
public class SimpleServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter wr = response.getWriter();
String uname = request.getParameter("unam");
HttpSession ses = request.getSession();
if (uname != "" && uname != "null") {
ses.setAttribute("userses", ses);
}
wr.println("In RequestHttp method your name is "+ uname);
wr.println("In Sesssion method your name is " + (String)ses.getAttribute("userses"));
}
}
`Apache Tom Cat 7：0错误严重：servlet [org.sathish.brains.SimpleServlet]的Servlet.service（）在路径[/ SimpleServletProject]的上下文中引发了异常java.lang.ClassCastException：org.apache.catalina.session .StandardSessionFacade不能在的javax.servlet在javax.servlet.http.HttpServlet.service（HttpServlet.java:621）铸造为java.lang.String在org.sathish.brains.SimpleServlet.doGet（SimpleServlet.java:37） . http.HttpServlet.service（HttpServlet.java:728）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:305）在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:210）在org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:243）在org.apache.catalina.core.ApplicationFilterChain .doFilter（ApplicationFilterChain.java:210）at org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrap） perValve.java:222）在org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:123）在org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:502）在org.apache.catalina .core.StandardHostValve.invoke（StandardHostValve.java:171）在org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:100）在org.apache.catalina.valves.AccessLogValve.invoke（AccessLogValve.java:953 ）在org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:118）在org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:409）在org.apache.coyote.http11.AbstractHttp11Processor . 进程（AbstractHttp11Processor.java:1044）org.apache.coyote.AbstractProtocol $ AbstractConnectionHandler.process（AbstractProtocol.java:607）at org.apache.tomcat.util.net.JIoEndpoint $ SocketProcessor.run（JIoEndpoint.java:313） at java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1145）at java.util.concurrent.ThreadPoolExecut或java.lang.Thread.run上的$ Worker.run（ThreadPoolExecutor.java:615）（Thread.java:744）
2 回答
看看这一行：
您将自己的会话作为属性传递 . 我想你要做的就是这样
你真的想把会话添加到会话中吗？我怀疑，你可能想要将属性设置为
uname. 更加注意你的代码 .并删除转换为String，这是不必要的 .
在尝试编写servlet代码之前，请认真学习Java的基础知识 .