topicserviceimpl.java

青年论坛设计想关代码

package com.ql.bbs.service.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import com.ql.bbs.model.Topic;
import com.ql.bbs.service.TopicService;
import com.ql.bbs.util.JdbcUtils;

public class TopicServiceImpl implements TopicService {

	public boolean addTopic(Topic topic) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		String sql = "insert into t_topic(title, context,userId,pid,date,categoryId) "+
					 "values(?,?,?,?,?)";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			
			pstmt.setString(1,topic.getTitle());
			pstmt.setString(2, topic.getContext());
			pstmt.setInt(3, topic.getUserId());
			pstmt.setInt(4, topic.getPid());
			//因为setDate必须set  java.sql包中的 Date,java.sql.Date是java.util.Date的子类  
			pstmt.setDate(5, new java.sql.Date(new java.util.Date().getTime()));
			pstmt.setInt(6, topic.getCategoryId());
			
			pstmt.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
			JdbcUtils.getInstance().close(con, pstmt, rs);
			return false;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return true;
	}

	public boolean delTopic(int id) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		String sql = "delete from t_topic where id = ?";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			pstmt.setInt(1, id);
			pstmt.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
			JdbcUtils.getInstance().close(con, pstmt, rs);
			return false;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return true;
	}

	public Topic findTopicById(int id) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		Topic topic = null;
		String sql = "select title, context,userId,pid,date,categoryId " +
					 "from t_topic where id=?";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			pstmt.setInt(1, id);
			rs = pstmt.executeQuery();
			
			if (rs.next()) {
				topic = new Topic();
				topic.setId(id);
				topic.setTitle(rs.getString("title"));
				topic.setContext(rs.getString("context"));
				topic.setUserId(rs.getInt("userId"));
				topic.setPid(rs.getInt("pid"));
				topic.setDate(rs.getDate("date"));
				topic.setCategoryId(rs.getInt("categoryId"));
			}
			
		} catch (Exception e) {
			e.printStackTrace();
			JdbcUtils.getInstance().close(con, pstmt, rs);
			return null;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return topic;
	}

	public List searchTopics() {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		List topicList = new ArrayList();
		String sql = "select id,title, context,userId,pid,date,categoryId " +
					 "from t_topic";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			rs = pstmt.executeQuery();
			
			while (rs.next()) {
				Topic topic = new Topic();
				topic.setId(rs.getInt("id"));
				topic.setTitle(rs.getString("title"));
				topic.setContext(rs.getString("context"));
				topic.setUserId(rs.getInt("userId"));
				topic.setPid(rs.getInt("pid"));
				topic.setDate(rs.getDate("date"));
				topic.setCategoryId(rs.getInt("categoryId"));
				topicList.add(topic);
			}
			
		} catch (Exception e) {
			e.printStackTrace();
			JdbcUtils.getInstance().close(con, pstmt, rs);
			return null;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return topicList;
	}

	public boolean updateTopic(Topic topic) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
	
		String sql = "update t_topic set title=?,context=?,date=?,categoryId=?";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			
			pstmt.setString(1,topic.getTitle());
			pstmt.setString(2, topic.getContext());
			pstmt.setInt(3, topic.getUserId());
			pstmt.setInt(4, topic.getPid());
			pstmt.setDate(5, new java.sql.Date(topic.getDate().getTime()));
			pstmt.setInt(6, topic.getCategoryId());
			
			pstmt.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
			JdbcUtils.getInstance().close(con, pstmt, rs);
			return false;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return true;
	}

}