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Java 如何在servlet中将控制权从服务转移到post方法?_Java_Servlets - Fatal编程技术网

Java 如何在servlet中将控制权从服务转移到post方法?

Java 如何在servlet中将控制权从服务转移到post方法?,java,servlets,Java,Servlets,我在service和post方法中编写了以下代码 protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { PrintWriter p = response.getWriter(); p.println("<html><body>"); p.println("<f

我在service和post方法中编写了以下代码

protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    PrintWriter p = response.getWriter();
    p.println("<html><body>");
    p.println("<form action = roomlog2 method = post>");
    p.println("<input type = submit value = back>");
    p.println("</form>");
    p.println("</body></html>");
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    response.sendRedirect("homepage.html");
 }

为什么post方法没有重定向到“homepage.html”?为什么我会出现异常?请有人告诉我错误

只需删除
service()
方法的实现,或者让它调用
super.service()
。这就是调用
doPost()
的方式。现在你根本不叫它

java.lang.NumberFormatException: null