有两个文件,index.html负责输入:
<input type="textbox" name="uname">
<input type="password" name="upass">
servlet query.java负责逻辑跳转:public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username = null, password=null;
String dataname=null, datapass=null;
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
//
username = request.getParameter("uname");
username = username.replaceAll(" ", "");
password = request.getParameter("upass");
password = password.replaceAll(" ", "");
if(username == null)
response.sendRedirect("/web30/error.html");
else
response.sendRedirect("/web30/success.html");
//
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
如果在index.html中输入的用户名为空的话怎么才能判断出来? if(username == null)好象不行,因为现在总是跳转到第二个页面success.html。
<input type="textbox" name="uname">
<input type="password" name="upass">
servlet query.java负责逻辑跳转:public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username = null, password=null;
String dataname=null, datapass=null;
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
//
username = request.getParameter("uname");
username = username.replaceAll(" ", "");
password = request.getParameter("upass");
password = password.replaceAll(" ", "");
if(username == null)
response.sendRedirect("/web30/error.html");
else
response.sendRedirect("/web30/success.html");
//
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
如果在index.html中输入的用户名为空的话怎么才能判断出来? if(username == null)好象不行,因为现在总是跳转到第二个页面success.html。
response.sendRedirect("/web30/success.html");
}else{
response.sendRedirect("/web30/error.html");
}
if( org.apache.commons.lang.StringUtils.isBlank(username))
response.sendRedirect("/web30/success.html");
}else{
response.sendRedirect("/web30/error.html");
}
判断应该到位了
response.sendRedirect("/web30/error.html");
}else {
response.sendRedirect("/web30/success.html");
}