1.使用单例来连接数据库 //数据库的连接使用单例来连接一次即可，执行完sql语句后如果没有结束就不能关流 不然后边就不能再去执行sql语句
public class JDBCUtils1 {
// 连接数据库的参数
private String driver= "com.mysql.jdbc.Driver";
private String url = "jdbc:mysql://localhost:3306/xinzhi666?useUnicode=true&characterEncoding=utf-8";
private String username = "root";
private String password = "root";
private static Connection conn;
private JDBCUtils1(){
try {
Class.forName(driver);
conn = DriverManager.getConnection(url, username, password);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
public static Connection getConnection(){
if(conn!=null){
new JDBCUtils1();
}
return conn;
}
public void relase(ResultSet resultSet, Statement statement,Connection connection){
try {
if(resultSet!=null){
resultSet.close();
}
if(statement!=null){
statement.close();
}
if(connection!=null){
connection.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
2.写注册的接口
public interface IUserInfoDao {
/**
* 注册 数据库中添加用户
* @param ui 用户实体类
* @return
*/
int addUser(UserInfo ui);
}
3.写注册的实现类
public class UserInfoDaoImpl implements IUserInfoDao {
@Override
public int addUser(UserInfo ui) {
int count = -1;
PreparedStatement pstat = null;
try {
String sql = "insert into user (username,password,age,phone) values (?,?,?,?)";
pstat = JDBCUtils.getConnection().prepareStatement(sql);
pstat.setString(1, ui.getUsername());
pstat.setString(2, ui.getPassword());
pstat.setInt(3, ui.getAge());
pstat.setString(4, ui.getPhone());
count = pstat.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
} finally{
JDBCUtils.relase(null, pstat, null);
}
return count;
}
2.注册的界面
<form action="regService.jsp" method="post">
用户名:<input type="text" name="username" /><br>
密码:<input type="text" name="password" /><br>
年龄:<input type="text" name="age" /><br>
手机号:<input type="text" name="phone" /><br>
<input type="submit" value="注册">
</form>
3.注册的后台逻辑
<%
request.setCharacterEncoding("UTF-8");
String username = request.getParameter("username");
String password = request.getParameter("password");
String age = request.getParameter("age");
String phone = request.getParameter("phone");
UserInfo ui = new UserInfo();
ui.setAge(Integer.parseInt(age));
ui.setUsername(username);
ui.setPassword(password);
ui.setPhone(phone);
UserInfoDaoImpl uidi = new UserInfoDaoImpl();
int count = uidi.addUser(ui);
if(count > 0){
response.sendRedirect("login.jsp");
}else{
request.setAttribute("info", "注册失败");
request.getRequestDispatcher("register.jsp").forward(request, response);
}
%>
登录功能
1.写登录的接口
/**** @param username 用户名* @param password 密码* @return 查询的数据*/User queryByUsernameAndPassword(String username,String password);
根据输入的账号密码来进入数据库查询
2.写登录的实现类
@Overridepublic User queryByUsernameAndPassword(String username, String password) {// 通过工具类获取连接对象 connectionConnection connection = BaseDao.getConnection();// 插入的sql语句String sql = "select id,username,password,age from user where username=? and password=?";PreparedStatement statement = null;ResultSet resultSet = null;User user = null;try {//获取statement对象statement = connection.prepareStatement(sql);statement.setString(1,username);statement.setString(2,password);resultSet = statement.executeQuery();if (resultSet.next()){int id = resultSet.getInt(1);String uname = resultSet.getString(2);String pw = resultSet.getString(3);int age = resultSet.getInt(4);user = new User(id, uname, pw, age);}} catch (SQLException throwables) {throwables.printStackTrace();}return user;}
3.写登录的界面
<form action="loginService.jsp" method="post">
用户名:<input type="text" name="username" />
密码:<input type="text" name="password" />
<input type="submit" value="登陆">
</form>
4.写登录的后台逻辑
<%
//设置页面请求编码格式
request.setCharacterEncoding("UTF-8");
//获取页面传过来的用户名和密码
String username = request.getParameter("username");
String password = request.getParameter("password");
// 登录逻辑
UserInfoDaoImpl uidi = new UserInfoDaoImpl();
User user = uidi.login(username, password);
// 获取年龄
ShowInfoDaoImpl showInfoDao = new ShowInfoDaoImpl();
Set<Integer> ages = showInfoDao.getAge();
if(user != null){
// 登陆成功
ShowInfoDaoImpl sidi = new ShowInfoDaoImpl();
List<User> uis = sidi.getUserList(-1);
// 域对象中设置属性（request域对象的特点）
request.setAttribute("uis", uis);
request.setAttribute("ages",ages );
request.getRequestDispatcher("show.jsp").forward(request, response);
}else{
// 登陆失败
request.setAttribute("info", "登陆失败");
request.getRequestDispatcher("login.jsp").forward(request, response);
}
%>
