web网页Eclipse,jsp+Servlet+javaBean，访问Mysql链接数据库
注意导完驱动包，还要在WEB-INF/lib下再放一份。
LogIn.jsp代码
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<%
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 'LogIn.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 method="post" action="Check.jsp"> -->
<form method="post" action="/servletStudy_20160302/ServletDemo">
用户名：<input type="text" size="20" name="name"><br>
密 码：<input type="password" size="20" name="password">
<input type="submit" value="登录" name="Submit"><br>
</form>
</body>
</html>
注意 action的“/servletStudy_20160302/ServletDemo”前面是项目名称后面是servlet类
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>servletStudy_20160302</display-name>
<servlet>
<servlet-name>ServletDemo</servlet-name>
<servlet-class>tju.chc.test.ServletDemo</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletDemo</servlet-name>
<url-pattern>/ServletDemo</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
</web-app>
还有一点，
下面是ServletDemo中的doPost方法
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
response.setCharacterEncoding("utf8");//这一句是为防止乱码
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><meta charset=\"gbk\"></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the POST method");
DatabaseBean databaseBean = new DatabaseBean();
String userName = request.getParameter("name");
String userPS = request.getParameter("password");
try{
if (databaseBean.logInUser(userName, userPS)) {
out.println(userName + ",sdfasdf你已经登陆成功！");
}
}catch(Exception e){
out.println("输入的用户名或者密码有误！");
}
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
DatabaseBean.java
package tju.chc.database;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class DatabaseBean {
private Connection connection = null;
private Statement statement = null;
private ResultSet resultSet = null;
public DatabaseBean(){
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mytest1", "root", "");
statement = connection.createStatement();
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public boolean logInUser(String userName,String userPassword){
boolean userExit = false;
String strSql = "select * from user where userId = '"+userName+"' and uPS = '" +userPassword+ "'";
try {
resultSet = statement.executeQuery(strSql);
if(resultSet.next()){
String userNam = resultSet.getString("userId");
String userPS = resultSet.getString("uPS");
System.out.println(userNam+","+userPS);
userExit = true;
connection.close();
return userExit;
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
try {
connection.close();
return false;
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
return userExit;
}
}