SSH框架开发的简单留言板系统

/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package lw.dao; import java.sql.PreparedStatement; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; import lw.idao.ILwContentDao; import lw.model.LwContent; /** * * @author student1 */ public class LwContentDao implements ILwContentDao { @Override public List<LwContent> findByPage(Integer pageSize, Integer pageNo) { Connection con = null; PreparedStatement pstmt = null; ResultSet rs = null; List<LwContent> list = new ArrayList<LwContent>(); try { con = ConnectDB.connect(); String sql = "select * from lw_content limit " + (pageNo - 1) * pageSize + "," + pageSize; pstmt=con.prepareStatement(sql); rs = pstmt.executeQuery(sql); LwContent lwContent = null; while (rs.next()) { lwContent = new LwContent(); lwContent.setContId(rs.getInt("cont_id")); lwContent.setContTitle(rs.getString("cont_title")); lwContent.setContContent(rs.getString("cont_content")); lwContent.setContDatetime(rs.getDate("cont_datetime")); list.add(lwContent); } } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } finally { try { rs.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { pstmt.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { con.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } } return list; } @Override public int findCount() { Connection con = null; PreparedStatement pstmt = null; ResultSet rs = null; int count = 0; try { con = ConnectDB.connect(); String sql = "select count(*) as count from lw_content"; pstmt=con.prepareStatement(sql); rs = pstmt.executeQuery(sql); if (rs.next()) { count = rs.getInt("count"); } } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } finally { try { rs.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { pstmt.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { con.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } } return count; } @Override public void insert(LwContent obj) { Connection con = null; PreparedStatement pstmt = null; try { con = ConnectDB.connect(); String sql = "insert into lw_content(cont_title,cont_content) values(?,?)"; pstmt=con.prepareStatement(sql); pstmt.setString(1, obj.getContTitle()); pstmt.setString(2, obj.getContContent()); pstmt.executeUpdate(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } finally { try { pstmt.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { con.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } } } @Override public void update(LwContent obj) { Connection con = null; PreparedStatement pstmt = null; try { con = ConnectDB.connect(); String sql = "update lw_content set cont_title=?,cont_content=? where cont_id=?"; pstmt=con.prepareStatement(sql); pstmt.setString(1, obj.getContTitle()); pstmt.setString(2, obj.getContContent()); pstmt.setInt(3, obj.getContId()); pstmt.executeUpdate(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } finally { try { pstmt.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { con.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } } } @Override public void delete(Integer id) { Connection con = null; PreparedStatement pstmt = null; try { con = ConnectDB.connect(); String sql = "delete from lw_content where cont_id=?"; pstmt=con.prepareStatement(sql); pstmt.setInt(1, id); pstmt.executeUpdate(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } finally { try { pstmt.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { con.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } } } @Override public LwContent findById(Integer id) { Connection con = null; PreparedStatement pstmt = null; ResultSet rs = null; LwContent lwContent = null; try { con = ConnectDB.connect(); String sql = "select * from lw_content where cont_id=?"; pstmt=con.prepareStatement(sql); pstmt.setInt(1, id); System.out.println(pstmt==null); rs = pstmt.executeQuery(); if (rs.next()) { lwContent = new LwContent(); lwContent.setContId(rs.getInt("cont_id")); lwContent.setContTitle(rs.getString("cont_title")); lwContent.setContContent(rs.getString("cont_content")); lwContent.setContDatetime(rs.getDate("cont_datetime")); } } catch (SQLException ex) { ex.printStackTrace(); Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } finally { try { rs.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { pstmt.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } try { con.close(); } catch (SQLException ex) { Logger.getLogger(LwContentDao.class.getName()).log(Level.SEVERE, null, ex); } } return lwConten