java web 登陆注册案例

package com.chao.daoimpl; import com.chao.bean.User; import com.chao.dao.UserDao; import com.chao.utils.C3P0Util; import com.chao.utils.DBCPUtil; import com.chao.utils.DBUtils; import org.apache.commons.dbcp.BasicDataSourceFactory; import javax.sql.DataSource; import java.io.FileInputStream; import java.io.InputStream; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.text.SimpleDateFormat; import java.util.Properties; /** * Created by Chao on 2016/12/11. */ public class UserDaoImpl implements UserDao { /** * 添加用户 * * @param user */ @Override public void addUser(User user) throws Exception { Connection conn = null; PreparedStatement ps = null; try { conn = DBUtils.getConnection(); ps = conn.prepareStatement("INSERT INTO users(name,pwd,phone,DATE) VALUES(?,?,?,?)"); ps.setString(1, user.getName()); ps.setString(2, user.getPwd()); ps.setString(3, user.getPhone()); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); String date = sdf.format(user.getDate()); ps.setString(4, date); int i = ps.executeUpdate(); } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加失败！"); } finally { DBUtils.closeAll(null, ps, conn); } } /** * 查询用户账号密码是否有效 * * @param user * @return * @throws Exception */ public User findUser(User user) throws Exception { Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; User u = null; try { conn = C3P0Util.getConnection(); ps = conn.prepareStatement("select * from users where name=? and pwd=?"); ps.setString(1, user.getName()); ps.setString(2, user.getPwd()); rs = ps.executeQuery(); if (rs.next()) { u = new User(); u.setId(rs.getInt(1)); u.setName(rs.getString(2)); u.setPwd(rs.getString(3)); u.setPhone(rs.getString(4)); u.setDate(rs.getTimestamp(5)); } } catch (Exception e) { e.printStackTrace(); } finally { C3P0Util.closeAll(rs, ps, conn); } return u; } /** * 查询用户名是否已经存在 * * @param name * @return */ public boolean findUserByName(String name) { Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; try { conn = DBCPUtil.getConnection(); ps = conn.prepareStatement("select * from users where name=?"); ps.setString(1, name); rs = ps.executeQuery(); if (rs.next()) {//如果账号存在 return true; } } catch (Exception e) { e.printStackTrace(); } finally { DBCPUtil.closeAll(rs, ps, conn); } return false; } }