你好，我用的是myeclipse。我是初学的javaee。我今天做了一个简单的用户、密码注册程序，用的是mysql数据库，请大家帮我看看我哪里出了问题。我的mysql数据库名为mydb，密码和用户名都是正确的，表名是users，表名和数据库名都是正确的。
JDBC类
package com.deng.jdbc;
import java.sql.*;
public class JDBCConnection {
public static void connect(String username,String password){
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb","root","ASD123zxc,./");
String sql="insert into users(username,password) values (?,?);";
PreparedStatement pre=con.prepareStatement(sql);
pre.setString(1, username);
pre.setString(2,password);
pre.executeUpdate();
pre.close();
con.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Servlet类
package com.deng.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.deng.jdbc.JDBCConnection;
public class MyServlet extends HttpServlet{
protected void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{
}
protected void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{
request.setCharacterEncoding("utf-8");
String username=request.getParameter("username");
String password=request.getParameter("password");
JDBCConnection.connect(username, password);
}
}
xml配置
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>hello</servlet-name>
<servlet-class>com.deng.servlet.MyServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>hello</servlet-name>
<url-pattern>/theta/index.jsp</url-pattern>
</servlet-mapping>
</web-app>
跳转后的页面delta.jsp
<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'delta.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
This is my delta page. <br>
</body>
</html>
主页面（也就是index.jsp，有文本框和提交按钮的这个页面）
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form name="former" method="post" action="/theta/delta.jsp">
<table border="0">
<tr>
<th>用户名</th>
<th><input type="text" name="username" value="${param.username}"></input></th>
<tr>
<th>密码</th>
<th><input type="password" name="password" value="${param.password}"></input></th>
</tr>
<tr>
<th align="center">
<input type="submit" name="sure" value="确定"></input>
</th>
</tr>
</table>
</form>
</body>
</html>
我不知道是哪里错了，当我点击确定按钮的时候，密码框和用户名里面的文字和密码无法插入到mysql数据库里，点击确定按钮时，mysql数据库没有数据，点击确定按钮后，我的mysql数据库还是没有数据。但是确实能够跳转到delta.jsp的页面，显示This is my delta page. 为什么我的代码只能跳转，却不能插入数据到数据库，这是为什么呢？
