（1）public interface IUserDAO /* 表示数据库的增加操作* param user* return* throws Exception*/public boolean doCreate(User user) throws Exception;public boolean doUpdate(User user) throws Exception;/* 表示删除操作，按编号删除* param id* return* throws Exception*/public boolean doDelete(int id) throws Exception;/* 表示数据库的查询操作* param id* return* throws Exception*/public User findById(intid) throws Exception;/* 查询的时候将返回一组对象* param keyWord* return* throws Exception*/public List findAll(StringkeyWord) throws Exception;（2）public class IUserDAOImpl implements IUserDAO private DataBaseConnection dbc = null;private Connection conn = null;public IUserDAOImpl()this.dbc = new DataBaseConnection();Overridepublic boolean doCreate(User user) throws Exception boolean flag = false;PreparedStatementpstmt = null;String sql = INSERT INTO user(name,sex,birthday) VALUES (?,?,?) ; try pstmt.setString(1, user.getName(); / 所有的内容从user 类中取出pstmt.setString(2, user.getSex();/ 所有的内容从 user 类中取出至少已经更新了一行flag = true; catch (Exception e) throw e; finally / 不管如何抛出，最终肯定是要进行数据库的关闭操作的 if (pstmt != null) try pstmt.close(); catch (Exception e1) return flag;Overridepublic boolean doDelete(int id) throws Exception boolean flag = false;PreparedStatementpstmt = null;String sql = DELETEFROM userWHERE id=? ;try pstmt.setInt(1, id); / 所有的内容从user 类中取出if (pstmt.executeUpdate() 0) /至少已经更新了一行flag = true; catch (Exception e) throw e; finally / 不管如何抛出，最终肯定是要进行数据库的关闭操作的 if (pstmt != null) try pstmt.close(); catch (Exception e1) return flag;Overridepublic boolean doUpdate(User user) throws Exception boolean flag = false;PreparedStatementpstmt = null;String sql = UPDA TE user SET name=?,sex=?,birthday=? WHERE id=?; try pstmt.setString(1, user.getName(); / 所有的内容从user 类中取出pstmt.setString(2, user.getSex();/ 所有的内容从user 类中取出if (pstmt.executeUpdate() 0) /至少已经更新了一行flag = true; catch (Exception e) throw e; finally / 不管如何抛出，最终肯定是要进行数据库的关闭操作的 if (pstmt != null) try pstmt.close(); catch (Exception e1) return flag;Overridepublic List findAll(String keyWord) throws Exception List all = new ArrayList(); PreparedStatementpstmt = null;String sql = SELECT id,name,sex,birthday FROM user WHERE name LIKE ? OR sex LIKE ? OR birthday LIKE ?;try pstmt.setString(1, % + keyWord + %);pstmt.setString(2, % + keyWord + %);pstmt.setString(3, % + keyWord + %);ResultSet rs = pstmt.executeQuery(); / 执行查询操作while (rs.next() User user = new User();user.setId(rs.getInt(1);user.setName(rs.getString(2);user.setSex(rs.getString(3);user.setBirthday(rs.getDate(4);all.add(user); / 所有的内容向集合中插入rs.close() ; catch (Exception e) throw e; finally / 不管如何抛出，最终肯定是要进行数据库的关闭操作的 if (pstmt != null) try pstmt.close(); catch (Exception e1) return all;Overridepublic User findById(intid) throws Exception User user =null ;PreparedStatementpstmt = null;String sql = SELECT id,name,sex,birthday FROM user WHERE id=?; try pstmt.setInt(1, id) ;ResultSet rs = pstmt.executeQuery(); / 执行查询操作if (rs.next() user= new User();user.setId(rs.getInt(1);user.setName(rs.getString(2);user.setSex(rs.getString(3);user.setBirthday(rs.getDate(4);rs.close() ; catch (Exception e) throw e; finally / 不管如何抛出，最终肯定是要进行数据库的关闭操作的 if (pstmt != null) try pstmt.close(); catch (Exception e1) return user;（3）public class DataBaseConnection private static final String DBPASS = mysqladmin ;private Connection conn = null ;public DataBaseConnection()try Class.forName(DBDRIVER); catch (ClassNotFoundException e) / TODO Auto -generatedcatch blocke.printStackTrace();try conn = DriverManager.getConnection(DBURL, DBUSER,DBPASS) ; catch (SQLException e) / TODO Auto -generatedcatch block e.printStackTrace();public Connection getConnection()return this.conn ;public void close()if(this.conn!=null)try catch (SQLException e) / TODO Auto -generatedcatch blocke.printStackTrace();