2018-03-09 创建用户注册模块

项目中JDBC代码的设计：

DAO:Data Access Object 数据访问对象

        将一组操作定义在一个类中

        每一个独立的功能定义一个方法

User模块登录和注册：

/**保存账号信息

*@param user 账号信息 

*@return int 添加记录数

*/

public int save(User user){

    String sql = "INSERT INTO ajia_user(username,password,email,phone,created,updated)VALUES(?,?,?,?,?,?)";

    int result = 0;

    Connection conn = null;

    try {

        conn = JdbcUtil.getConn();

        PreparedStatement pstmt = conn.prepareStatement(sql);

        pstmt.setString(1, user.getUserName());

        pstmt.setString(2, user.getPassword());

        pstmt.setString(3, user.getEmail());

        pstmt.setString(4, user.getPhone());

        pstmt.setTimestamp(5, user.getCreated());

        pstmt.setTimestamp(6, user.getUpdated());

        result = pstmt.executeUpdate();

    } catch (SQLException e) {

        e.printStackTrace();

    }finally{

          JdbcUtil.close(conn);

} return result;

}

根据账号查询 验证账号是否被占用:

/**

* 根据账号查询 验证账号是否被占用

* @param userName 账号

* @return boolean 是否存在

*/

public boolean findByUserName(String userName){

    String sql = "SELECT username FROM ajia_user WHERE username=?";

    boolean isUsed = false;

    Connection conn = null;

    try {

        conn = JdbcUtil.getConn();

        PreparedStatement pstmt = conn.prepareStatement(sql);

        pstmt.setString(1, userName);

        ResultSet rs = pstmt.executeQuery();

        if(rs.next()){ isUsed = true;

      } } catch (SQLException e) {

            e.printStackTrace();

        }finally{

        JdbcUtil.close(conn);

        } return isUsed;

}