我的数据库不是在jsp页面上简单地连接到netbeans上的

Question

以下是显示wheather数据库已连接或

不，我正在使用mysql工作台，netbeans.It显示没有连接

而glassfish服务器正在显示一些警告，这些警告显示在代码之后。

 code

 <%@page import="java.sql.DriverManager"%>
 <%@page import="java.sql.Connection"%>
 <%@page contentType="text/html" pageEncoding="UTF-8"%>
 <!DOCTYPE html>
 <html>
   <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>JSP Page</title>
  </head>
  <body>
    <%
    Connection conn = null;

    try{
         Class.forName("com.mysql.jdbc.Driver");
     conn =DriverManager.getConnection
     ("jdbc:mysql://localhost:3306/userpass?zeroDateTimeBehavior                                                          
             =convertToNull","root", "root");
         if(conn!=null)
         {
             out.print("connected to database successfully");
         }

      }catch(Exception e)
      {
       out.print("not connected to database");
    }

    %>
   </body>
   </html>

   <warning and info*/
   Info:   Loading application __admingui done in 7,651  ms
   Warning:   Context path from ServletContext:  differs from path from      
         bundle:/
  Info:   Redirecting to /index.jsf
  Info:   Admin Console: Initializing Session Attributes...
 Warning:   Could not open/create prefs root node Software\JavaSoft\Prefs at        
 root 0x80000002. Windows RegCreateKeyEx(...) returned error code 5.
 Warning:   Cannot create update center Image for C:\Program   
 Files\glassfish->4.1.1; Update Center functionality will not be available       
 in Admin Console

Answer 1

尝试一下，也许这是语法错误，也可以检查是否有正确的jar文件-

Connection conn = null;

try{
     Class.forName("com.mysql.jdbc.Driver");
 conn =DriverManager.getConnection
 ("jdbc:mysql://localhost:3306/userpass","root", "root"); //removed after userpass
     if(conn!=null)
     out.println("connected to database successfully");
     else
     out.println("not connected to database");

  }catch(Exception e)
  {
   out.println(e);
 }

Answer 2

首先，我要说用jsp编写数据库代码不是code.All的好方法，数据库代码和业务逻辑必须用servlet编写，或者普通的java class.Jsp是视图，经过servlet处理后，我们可以使用jsp显示输出。

This is just a warning, you can ignore it if you want.

引发此警告是因为您的上下文中可能有一个前导斜杠(即/) - glassfish-web.xml中的根(应该位于WAR的web.xml文件夹中)。

如果删除前面的斜杠，您可能会删除警告，因此glassfish-web.xml看起来类似于以下内容：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE glassfish-web-app PUBLIC "-//GlassFish.org//DTD GlassFish     Application Server 3.1 Servlet 3.0//EN" "http://glassfish.org/dtds/glassfish-web-app_3_0-1.dtd">
<glassfish-web-app error-url="">
<context-root>SalutationApp-war</context-root>
 </glassfish-web-app>



I hope I helped u.