基于JavaEE+bootstrap完成的小型博客论坛网站，可以实现添加帖子，查看帖子，删除帖子等功能.zip

package dao; import entity.Topic; import utils.DBUtils; import java.sql.*; import java.util.ArrayList; import java.util.List; public class TopicDao { public static Integer add(Topic t)throws SQLException{ PreparedStatement prep; String sql="INSERT INTO topic(`ptext`,`pauthor`,`ptime`) VALUE(?,?,?)"; Connection connection= DBUtils.getConnection(); prep=connection.prepareStatement(sql); prep.setString(1,t.getpText()); prep.setString(2,t.getpAuthor()); prep.setTimestamp(3, (Timestamp) t.getpTime()); prep.executeUpdate(); DBUtils.release(prep); prep=connection.prepareStatement("SELECT MAX(pid) as p from topic"); ResultSet rs=prep.executeQuery(); if(rs.next()){ return rs.getInt("p"); } return null; } public static List<Topic> getByPid(int id) throws SQLException{ Connection connection=DBUtils.getConnection(); PreparedStatement preparedStatement; String sql="SELECT * FROM topic WHERE pid=?"; List<Topic> topics=new ArrayList<Topic>(); preparedStatement=connection.prepareStatement(sql); preparedStatement.setInt(1,id); ResultSet rs=preparedStatement.executeQuery(); if(rs.next()){ Topic topic=new Topic(); topic.setPid(rs.getInt("pid")); topic.setpText(rs.getString("ptext")); topic.setpAuthor((rs.getString("pauthor"))); topic.setpTime(rs.getTimestamp("ptime")); topic.setpCount(rs.getInt("pcount")); topics.add(topic); } return topics; } //查看全部topic public static List<Topic> getAllTopic() throws SQLException{ Connection connection=DBUtils.getConnection(); PreparedStatement preparedStatement; String sql="SELECT topic.pid,topic.ptext,topic.pauthor,topic.ptext,cnt.pcount,topic.ptime FROM topic LEFT JOIN (SELECT pid,count(1) as pcount FROM Invitation GROUP BY pid) cnt on cnt.pid=topic.pid ORDER BY topic.pid DESC "; List<Topic> topics=new ArrayList<Topic>(); preparedStatement=connection.prepareStatement(sql); ResultSet rs=preparedStatement.executeQuery(); while(rs.next()){ Topic topic=new Topic(); topic.setPid(rs.getInt("pid")); topic.setpText(rs.getString("ptext")); topic.setpAuthor((rs.getString("pauthor"))); topic.setpTime(rs.getTimestamp("ptime")); topic.setpCount(rs.getInt("pcount")); topics.add(topic); } return topics; } //更新pcount /* public static void updateCount(int pid,int count) throws SQLException{ Connection connection=DBUtils.getConnection(); PreparedStatement preparedStatement; String sql="UPDATE topic set pcount=? WHERE pid=?"; preparedStatement=connection.prepareStatement(sql); preparedStatement.setInt(1,count); preparedStatement.setInt(2,pid); preparedStatement.executeUpdate(); DBUtils.release(preparedStatement); }*/ }