编辑“淘特Jsp Cms二次开发说明”（章节）

==实例操作==
以下例子是一个完整的二次开发数据库类的例子(一个广告操作的数据库类)：
<pre>
package tot.dao.jdbc;
import tot.dao.AbstractDao;
import tot.db.DBUtils;
import tot.bean.*;
import tot.exception.ObjectNotFoundException;
import tot.exception.DatabaseException;
import java.sql.*;
import java.util.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
 *
 * @author tot
 */
public class AdDaoImplJDBC extends AbstractDao{
    private static Log log = LogFactory.getLog(AdDaoImplJDBC.class);
    /** Creates a new instance of AdDaoImplJDBC */
    public AdDaoImplJDBC() {
    }
/** 广告添加 */
    public boolean add(String title,String content,Timestamp moditime){
        Connection conn = null;
        PreparedStatement ps = null;
        boolean returnValue=true;
        String sql="insert into t_ad(Title,Content,ModiTime) values(?,?,?)";
        try{
            conn = DBUtils.getConnection();
            ps=conn.prepareStatement(sql);            
            ps.setString(1,title);
            ps.setString(2,content);
            ps.setTimestamp(3,moditime);
            if(ps.executeUpdate()!=1) returnValue=false;
        } catch(SQLException e){
            log.error("add error",e);
        } finally{
            DBUtils.closePrepareStatement(ps);
            DBUtils.closeConnection(conn);
        }
        return returnValue;
    }
    /*
     * 广告修改
     */
    public boolean mod(int id,String title,String content,Timestamp moditime){
        Connection conn = null;
        PreparedStatement ps = null;
        boolean returnValue=true;
        String sql="update t_ad set Title=?,Content=?,ModiTime=? where id=?";
        try{
            conn = DBUtils.getConnection();
            ps=conn.prepareStatement(sql);
            ps.setString(1,title);
            ps.setString(2,content);
            ps.setTimestamp(3,moditime);
            ps.setInt(4,id);
            if(ps.executeUpdate()!=1) returnValue=false;
        } catch(SQLException e){
            log.error("mod error",e);
        } finally{
            DBUtils.closePrepareStatement(ps);
            DBUtils.closeConnection(conn);
        }
        return returnValue;
    }    
    /* 广告删除 */
    public boolean del(int id) throws ObjectNotFoundException,DatabaseException{
        return exe("delete from t_ad where id="+id);
    }
    /* 
     * 广告分页调用 
     * @param currentpage 当前页数
     * @param pagesize	  每页记录数
    */
    public Collection getAdList_Limit(int currentpage,int pagesize){
        if(DBUtils.getDatabaseType() == DBUtils.DATABASE_MYSQL){
            StringBuffer sql=new StringBuffer(512);
            sql.append("select id,Title,ModiTime from t_ad");
            return getDataList_mysqlLimit(sql.toString(),"id,Title,ModiTime",pagesize,(currentpage-1)*pagesize);
        } else if (DBUtils.getDatabaseType() == DBUtils.DATABASE_SQLSERVER) {
            StringBuffer sql=new StringBuffer(512);
            sql.append("SELECT TOP ");
            sql.append(pagesize);
            sql.append(" id,Title,ModiTime FROM t_ad WHERE (id <=(SELECT MIN(id) FROM (SELECT TOP ");
            sql.append((currentpage-1)*pagesize+1);
            sql.append(" id  FROM t_ad");
            sql.append(" ORDER BY id DESC) AS t))");
            sql.append(" ORDER BY id DESC");
            return getData(sql.toString(),"id,Title,ModiTime");
        } else{
            StringBuffer sql=new StringBuffer(512);
            sql.append("select id,Title,ModiTime from t_ad");
            return getDataList_Limit_Normal(sql.toString(),"id,Title,ModiTime",pagesize,(currentpage-1)*pagesize);
        }
    }
    /** 获取某一条广告记录 ,并以DataField类结果存放，读取时采用DataField.getFieldValue("字段名称")方法*/
    public DataField getGuestBook(int id){
        return getFirstData("select id,Title,ModiTime from t_ad where id="+id,"id,Title,ModiTime");
    }
    /*记录个数*/
    public int getTotalCount(){
        StringBuffer sql=new StringBuffer(512);
        sql.append("select count(*) from t_ad");
        return(this.getDataCount(sql.toString()));
    }
}

常见的前台分页调用部分代码：
开始要import系统常用的包
<%@ page import="tot.exception.*"%>
<%@ page import="tot.util.*" %>
<%@ page import="tot.bean.*" %>
<%@ page import="tot.dao.DaoFactory" %>
..............

<%
  int CurrentPage=RequestUtil.getInt(request,"page");//当前页数
  int PageSize=20;//每页显示个数
  TotalNum=DaoFactory.getAdDAO().getTotalCount(categoryid);//总记录个数
  PageNum=(TotalNum-1+PageSize)/PageSize;//计算总页数
  ArrayList list=(ArrayList)DaoFactory.getAdDAO().getAdList_Limit(CurrentPage,PageSize);//获取记录
  for (Iterator iter = list.iterator(); iter.hasNext(); ) {//遍历记录
  	DataField df=(DataField)iter.next();//一行记录
	String id=df.getFieldValue("id");//读取字段id
	int AdType=Integer.parseInt(df.getFieldValue("AdType"));//读取字段AdType
  }
%>
</pre>