import java.sql.Connection;  
import java.sql.DriverManager;  
import java.sql.ResultSet;  
import java.sql.SQLException;  
import java.sql.Statement;  
  
public class BaseDao {  
    Connection con = null;  
    Statement st = null;  
    ResultSet rs = null;  
  
    /** 
     * 获得联接 
     *  
     * @return 
     */  
    public Connection getConnection() {  
        try {  
            // 加载驱动，这一句也可写为：Class.forName("com.mysql.jdbc.Driver");   
            Class.forName("com.mysql.jdbc.Driver").newInstance();  
  
            // 建立到MySQL的连接   
            con = DriverManager.getConnection("jdbc:mysql://localhost:3306/money_note?characterEncoding=UTF-8", "root", "root");  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
        return con;  
    }  
  
    /** 
     * 关闭数据源 
     */  
    public void CloseConnection(Connection con, Statement s, ResultSet rs) {  
        try {  
            if (rs != null) {  
                rs.close();  
            }  
            if (s != null) {  
                s.close();  
            }  
            if (con != null) {  
                con.close();  
            }  
        } catch (SQLException e) {  
            e.printStackTrace();  
        }  
    }  
}  

import java.sql.Connection;  
import java.sql.ResultSet;  
import java.sql.SQLException;  
import java.sql.Statement;  
  
  
public class Test extends BaseDao {  
  
    Connection con = null;  
    Statement st = null;  
    ResultSet rs = null;  
  
    /** 
     * 查询数据 
     */  
    public void find() {  
        con = getConnection();  // 获得联接  
        try {  
            st = con.createStatement();  
            rs = st.executeQuery("select * from app_user");  
            while (rs.next()) {  
                System.out.println("编号：" + rs.getInt("uuid") + ", 姓名：" + rs.getString("userName") + ", 性别：" + rs.getString("sex") + ", 生日：" + rs.getString("birthday") + ", 住址：" + rs.getString("address"));  
            }  
        } catch (SQLException e) {  
            e.printStackTrace();  
        } finally {  
            CloseConnection(con, st, rs);   // 关闭联接  
        }  
    }  
  
    /** 
     * 添加数据 
     */  
    public void add() {  
        con = getConnection();  
        try {  
            st = con.createStatement();  
            int result = st.executeUpdate("insert into app_user(userName,passWord,sex,birthday,address) values('赵丽颖','wanying','女','1992-02-03','北京市')");  
            if (result > 0) {  
                System.out.println("插入成功");  
            } else {  
                System.out.println("插入失败");  
            }  
        } catch (SQLException e) {  
            System.out.println("插入失败");  
            e.printStackTrace();  
        } finally {  
            CloseConnection(con, st, rs);  
        }  
    }  
  
    /** 
     * 更新数据 
     */  
    public void update() {  
        con = getConnection();  
        try {  
            st = con.createStatement();  
            int result = st.executeUpdate("update app_user set address = '河南' where uuid = '3'");  
            if (result > 0) {  
                System.out.println("更新成功");  
            } else {  
                System.out.println("更新失败");  
            }  
        } catch (SQLException e) {  
            e.printStackTrace();  
        } finally {  
            CloseConnection(con, st, rs);  
        }  
    }  
  
    /** 
     * 删除数据 
     */  
    public void delete() {  
        con = getConnection();  
        try {  
            st = con.createStatement();  
            int result = st.executeUpdate("delete from app_user where uuid = '3'");  
            if (result > 0) {  
                System.out.println("删除成功");  
            } else {  
                System.out.println("删除失败");  
            }  
        } catch (SQLException e) {  
            e.printStackTrace();  
        } finally {  
            CloseConnection(con, st, rs);  
        }  
    }  
  
    public static void main(String[] args) {  
        Test test = new Test();  
        //test.add();  
        // test.update();  
         test.delete();  
        test.find();  
  
    }  
  
}