newsdao.java

新闻管理系统

/*
 * Created on 2007-4-16
 *
 * TODO To change the template for this generated file go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
package cn.edu.zucc.news.model;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

/**
 * @author wengwy
 * 
 * TODO To change the template for this generated type comment go to Window -
 * Preferences - Java - Code Style - Code Templates
 */
public class NewsDAO {
	private Connection conn = null;

	private Statement st = null;

	private Statement st2 = null;

	public NewsDAO() {
		try {
			Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
			conn = DriverManager
					.getConnection(
							"jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=j2ee_news",
							"sa", "sa");
			st = conn.createStatement();
			st2 = conn.createStatement();
		} catch (Exception ex) {
			ex.printStackTrace();
		}
	}

	public synchronized void release() {
		if (st != null) {
			try {
				st.close();
			} catch (Exception e) {
			}
		}
		if (st2 != null) {
			try {
				st2.close();
			} catch (Exception e) {
			}
		}

		if (conn != null) {
			try {
				conn.close();
			} catch (Exception e) {
			}
		}

	}

	public synchronized List loadAllNewsType() throws Exception {
		List result = new ArrayList();
		try {
			ResultSet rs = st.executeQuery("select * from tb_news_types");
			while (rs.next()) {
				NewsType newstype = new NewsType();
				newstype.setNewsTypeId(rs.getString("news_type_id"));
				newstype.setNewsTypeName(rs.getString("news_type_name"));
				newstype.setListOrd(rs.getInt("list_ord"));
				result.add(newstype);
			}
		} catch (Exception ex) {
			ex.printStackTrace();
			throw new Exception("数据库查询错误");
		}
		return result;
	}

	public synchronized List loadAllNews() throws Exception {
		List result = new ArrayList();
		try {
			ResultSet rs = st.executeQuery("select * from tb_news_types");
			while (rs.next()) {
				NewsType newstype = new NewsType();
				newstype.setNewsTypeId(rs.getString("news_type_id"));
				newstype.setNewsTypeName(rs.getString("news_type_name"));
				newstype.setListOrd(rs.getInt("list_ord"));
				result.add(newstype);
			}
			rs.close();

			for (int i = 0; i < result.size(); i++) {
				NewsType newstype = (NewsType) result.get(i);
				rs = st
						.executeQuery("select  * from tb_news_list where remove_date is  null and news_type_id='"
								+ newstype.getNewsTypeId()
								+ "' order by create_date desc");

				while (rs.next()) {
					News news = new News();
					news.setCreateDate(rs.getDate("create_date"));
					news.setIsurl(rs.getString("is_url"));
					news.setNewsAutor(rs.getString("news_author"));
					news.setNewsContent(rs.getString("news_content"));
					news.setNewsid(rs.getString("news_id"));
					news.setNewsTitle(rs.getString("news_title"));
					news.setNewsTypeId(rs.getString("news_type_id"));
					news.setReadcount(rs.getInt("read_count"));
					news.setRecentReadDate(rs.getDate("recent_read_date"));
					newstype.getNewsList().add(news);
				}
				rs.close();

			}
		} catch (Exception ex) {
			ex.printStackTrace();
			throw new Exception("数据库查询错误");
		}
		return result;
	}

	public synchronized void addNewstype(NewsType newstype) throws Exception {
		try {

			String sql = "insert into tb_news_types(news_type_id,news_type_name,list_ord) values('"
					+ newstype.getNewsTypeId()
					+ "','"
					+ newstype.getNewsTypeName()
					+ "',"
					+ newstype.getListOrd()
					+ ")";
			st.execute(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
			throw new Exception("数据库错误");
		}

	}

	public synchronized void saveNewstype(NewsType newstype) throws Exception {
		try {

			String sql = "update tb_news_types set news_type_name='"
					+ newstype.getNewsTypeName() + "',list_ord="
					+ newstype.getListOrd() + " where news_type_id='"
					+ newstype.getNewsTypeId() + "'";
			st.execute(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
			throw new Exception("数据库错误");
		}

	}

	public synchronized void delNewstype(String newstypeid) throws Exception {
		try {
			ResultSet rs = st
					.executeQuery("select * from tb_news_types where news_type_id='"
							+ newstypeid + "'");
			if (!rs.next()) {
				throw new Exception("新闻类别不存在");
			}
			String sql = "delete from tb_news_types where news_type_id='"
					+ newstypeid + "'";
			st.execute(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
			throw new Exception("数据库错误");
		}
	}

	public synchronized NewsType readNewstype(String newstypeid)
			throws Exception {
		NewsType result = null;
		try {
			ResultSet rs = st
					.executeQuery("select * from tb_news_types where news_type_id='"
							+ newstypeid + "'");
			if (rs.next()) {
				result = new NewsType();
				result.setNewsTypeId(rs.getString("news_type_id"));
				result.setNewsTypeName(rs.getString("news_type_name"));
				result.setListOrd(rs.getInt("list_ord"));
			}
		} catch (Exception ex) {
			ex.printStackTrace();
			throw new Exception("数据库查询错误");
		}

		return result;

	}

	public synchronized void addNews(News news) throws Exception {
		try {

			String sql = "insert into tb_news_list(news_id,news_title,news_author,create_date,news_content,is_url,read_count,news_type_id)"
					+ " values('"
					+ news.getNewsid()
					+ "','"
					+ news.getNewsTitle()
					+ "','"
					+ news.getNewsAutor()
					+ "',getdate(),'"
					+ news.getNewsContent()
					+ "','"
					+ news.getIsurl() + "',0,'" + news.getNewsTypeId() + "')";
			st.execute(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
			throw new Exception("数据库错误");
		}

	}

	public synchronized void saveNews(News news) throws Exception {
		try {
			String sql = sql = "update tb_news_list set news_title='"
					+ news.getNewsTitle() + "',news_content='"
					+ news.getNewsContent() + "',is_url='" + news.getIsurl()
					+ "' where news_id='" + news.getNewsid() + "'";
			System.out.println(sql);
			st.execute(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
			throw new Exception("数据库错误");
		}

	}

	public synchronized void delNews(String newsid) throws Exception {
		try {
			ResultSet rs = st
					.executeQuery("select * from tb_news_list where news_id='"
							+ newsid + "'");
			if (!rs.next()) {
				throw new Exception("新闻条目不存在");
			}
			String sql = "delete from tb_news_list where news_id='" + newsid
					+ "'";
			st.execute(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
			throw new Exception("数据库错误");
		}
	}

	public synchronized News readNews(String newsid) throws Exception {
		News result = null;
		try {
			ResultSet rs = st
					.executeQuery("select * from tb_news_list where news_id='"
							+ newsid + "'");
			if (rs.next()) {
				result = new News();
				result.setCreateDate(rs.getDate("create_date"));
				result.setIsurl(rs.getString("is_url"));
				result.setNewsAutor(rs.getString("news_author"));
				result.setNewsContent(rs.getString("news_content"));
				result.setNewsid(rs.getString("news_id"));
				result.setNewsTitle(rs.getString("news_title"));
				result.setNewsTypeId(rs.getString("news_type_id"));
				result.setReadcount(rs.getInt("read_count"));
				result.setRecentReadDate(rs.getDate("recent_read_date"));
			}
		} catch (Exception ex) {
			ex.printStackTrace();
			throw new Exception("数据库查询错误");
		}

		return result;

	}

	public synchronized void incReadCount(String newsid) throws Exception {
		try {
			st
					.execute("update tb_news_list set read_count=read_count+1,recent_read_date=getdate() where news_id='"
							+ newsid + "'");
		} catch (Exception ex) {
			ex.printStackTrace();
			throw new Exception("数据库查询错误");
		}
	}

}