newslogicbean.java

一个Filter的实例

package org.langsin.news.logic;

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

import org.langsin.news.comm.DataSource;
import org.langsin.news.data.NewsDataBean;

public class NewsLogicBean {
	private int allRows;
	private int curPage=1;
	private int rowPerPage=5;
	private int allPages;

public int getCurPage() {
		return curPage;
	}
	public void setCurPage(int curPage) {
		this.curPage = curPage;
	}
	public int getAllPages() {
		return allPages;
	}
	public int getAllRows() {
		return allRows;
	}
	public int getRowPerPage() {
		return rowPerPage;
	}
@SuppressWarnings("unchecked")
public List findAll(){
	List list=new ArrayList();
	Statement st=null;
	ResultSet rs=null;
	try {
		st=DataSource.getConnection().createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
		rs=st.executeQuery("select newsid,newstitle,newscontent,newscount,newsdate from news order by newsdate desc");
		rs.last();
		this.allRows=rs.getRow();
		if(this.allRows%this.rowPerPage==0){
			this.allPages=this.allRows/this.rowPerPage;
		}else{
			this.allPages=this.allRows/this.rowPerPage+1;
		}
		if(this.curPage==1){
			rs.beforeFirst();
		}else{
			rs.absolute((this.curPage-1)*this.rowPerPage);
		}
		int i=0;
		while(rs.next()&&i<this.rowPerPage){
			NewsDataBean bean=new NewsDataBean();
			bean.setNewsid(rs.getString(1));
			bean.setNewstitle(rs.getString(2));
			bean.setNewscontent(rs.getString(3));
			bean.setNewscount(rs.getString(4));
			bean.setNewsdate(rs.getString(5));
			list.add(bean);
			i++;
			
		}
	} catch (SQLException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
	return list;
}
	public static void main(String[] args) {
		// TODO Auto-generated method stub
    List list=new NewsLogicBean().findAll();
    System.out.println(list.size());
	}

}