listallfilter.java

java web网络编程示例,原代码资源

package edu.liusong.filter;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

import edu.liusong.dao.ArticleDAO;
import edu.liusong.dao.BoardDAO;
import edu.liusong.dao.NewsDAO;

public class ListAllFilter implements Filter{
	protected FilterConfig config = null;

	public void destroy() {
		config = null;
	}

	public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException,
			ServletException {
		HttpServletRequest request = (HttpServletRequest) arg0;		
		if(request.getAttribute("boardList")==null){
			//左边导航栏信息初始化
			request.setAttribute("boardList", new BoardDAO().getBoards());
		}
		if(request.getAttribute("newsList")==null){
			//右侧通知初始化
			request.setAttribute("newsList", new NewsDAO().getTopNews());
		}
		/**   分页初始化   **/
		long bid = 0;
		int pageSize=Integer.parseInt(config.getInitParameter("pageSize"));
		int topage;
		if(request.getParameter("bid")!=null){
			bid=Long.parseLong(request.getParameter("bid"));
		}		
		String strpage=request.getParameter("strpage");
		if(strpage==null){
			topage=1;
		}			
		else{
			topage=Integer.parseInt(strpage);
			if(topage<1)
				topage=1;
		}
		request.setAttribute("articleList", new ArticleDAO().getByPage(bid, pageSize, topage,"审核通过"));
		request.setAttribute("bid", bid);
		request.setAttribute("prePage", topage-1);
		request.setAttribute("nextPage", topage+1);
		arg2.doFilter(arg0, arg1);
	}

	public void init(FilterConfig arg0) throws ServletException {
		config = arg0;
	}
}