message.java

用J2EE开发的网站,可以应用到图书馆,图书超市

package ksnb;
import javax.sql.*;
import java.sql.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.text.*;
public class Message {
    private conn c=null;
    private Connection con=null;
    private Statement stm=null;
    private ResultSet rs=null;

    Collection ret=new ArrayList();
    public Message()
    {
        try {
            c = new conn();
            con = c.getConncetion();

        } catch (Exception e) {
            System.out.println(e.toString());
        }
    }
    private static String convert( String str )
    {
        try
        {
            byte[] bytesStr=str.getBytes( "ISO-8859-1" ) ;
            return new String( bytesStr, "gb2312" ) ;
        }
        catch( Exception ex)
        {
            return str ;
        }
    }

    public Collection query(String id) {
        System.out.println("id" + id);
        int Id = Integer.parseInt(id);
        System.out.println(Id);
        String sql = "select * from Shop_Gbook_info where Product_id= '" + Id +
                     "' order by Date_time desc";
        //String sql="select * from Shop_Gbook_info";
        try {
            stm = con.createStatement();
            rs = stm.executeQuery(sql);
            String Content = null;
            String Author = null;
            java.sql.Date date = null;
            int Book=0;

             //int cmd=Integer.parseInt(request.getParameter("cmd"));
             while(rs.next())
               {
                   Book=rs.getInt("Product_id");
                   Content=rs.getString("Content");
                   Author=rs.getString("Author");
                   date=rs.getDate("Date_time");
                   MessageBean message=new MessageBean();
                   message.setContent(Content);
                   message.setAuthor(Author);
                   message.setDatetime(date);
                   message.setBook(Book);
                   ret.add(message);

              }

              rs.close();

              return ret;


        } catch(Exception e){System.out.println(e);}

        return ret;
    }

    public int insert(HttpServletRequest request)
    {
        int id=Integer.parseInt(request.getParameter("cmd1"));
        String sql="insert into Shop_Gbook_info(Product_id,Content,Author,[Level],Date_time) values(?,?,?,?,?)";
        String name=convert(request.getParameter("username"));
        String content=convert(request.getParameter("content"));
        //从session中获取出用户是否登陆，对[level]进行赋值
        int i=0;
       //java.sql.Date date=null;
         //提取出从jsp页面中的值
         if(name==null)
             name="过客";
         try
         {
             DateFormat dateFormatter = DateFormat.getDateTimeInstance(DateFormat.LONG,DateFormat.LONG);
             // 取得系统时间
             java.util.Date utilDate = new java.util.Date();
             // 转换成数据库时间
             java.sql.Date date = new java.sql.Date(utilDate.getTime());
             PreparedStatement stm=con.prepareStatement(sql);
             stm.setInt(1,id);//从页面上提取出书的id
             stm.setString(2,content);
             stm.setString(3,name);
             stm.setInt(4,i);
             stm.setDate(5,date);
             stm.execute();
         }
         catch(Exception e){System.out.println(e);}

    return 1;
}



}