srarchreadercontroller.java

学习jsp时做的一个书馆

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Vector;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import library.DBConnection;


@SuppressWarnings("serial")
public class SrarchReaderController extends Controller {
	 @SuppressWarnings("unchecked")
	public void doPost (HttpServletRequest req,
				HttpServletResponse res) throws ServletException, IOException {
		HttpSession session = req.getSession();
		//req.setCharacterEncoding("GB2312"); 
		
		String id =  new String(req.getParameter("number").getBytes("ISO-8859-1"),"GB2312");
		String stuno = new String(req.getParameter("stuno").getBytes("ISO-8859-1"),"GB2312");
		String name =new String( req.getParameter("name").getBytes("ISO-8859-1"),"GB2312");
		String xueyuan = new String(req.getParameter("xueyuan").getBytes("ISO-8859-1"),"GB2312");
		String zhuanye = new String(req.getParameter("zhuanye").getBytes("ISO-8859-1"),"GB2312");
	
		session = req.getSession();
	
		boolean find = true;
		
		if(id.equals("")&&stuno.equals("")&&
				name.equals("")&&xueyuan.equals("")&&
				zhuanye.equals("")){
			    find = false;
		}
		try{
			if(find==false){
				res.sendRedirect("../admin/searchreader.jsp?jieguo=failed");
			}else{
				String sql = "select * from reader where ";
				if(!id.equals("")){
					sql += "readerid = '"+id+"'";
				}
				if(!stuno.equals("")&&!sql.endsWith("where ")){
					sql += "and stuno = '"+stuno+"'";
				}
				if(!stuno.equals("")&&sql.endsWith("where ")){
					sql += "stuno = '"+stuno+"'";
				}
				if(!name.equals("")&&!sql.endsWith("where ")){
					sql += "and name like '%"+name+"%'";
				}
				if(!name.equals("")&&sql.endsWith("where ")){
					sql += " name like '%"+name+"%'";
				}
				if(!xueyuan.equals("")&&!sql.endsWith("where ")){
					sql += "and xueyuan = '"+xueyuan+"'";
				}
				if(!xueyuan.equals("")&&sql.endsWith("where ")){
					sql += " xueyuan = '"+xueyuan+"'";
				}
				if(!zhuanye.equals("")&&!sql.endsWith("where ")){
					sql += "and zhuanye = '"+zhuanye+"'";
				}
				if(!zhuanye.equals("")&&sql.endsWith("where ")){
					sql += " zhuanye = '"+zhuanye+"'";
				}
				DBConnection connection = DBConnection.Instance();
				ResultSet w = null;
				
				Vector vector = new Vector();
				w = connection.runQuery(sql);
				while(w.next()){
					vector.add(w.getString("readerid"));
					//res.sendRedirect("../admin/new.jsp?l="+w.getString("readerid"));
				}
				session.setAttribute("rdsearchresult", vector);
				res.sendRedirect("../admin/readsearchresult.jsp");
			}
			
		}catch(Exception e){
			 sendErrorRedirect(req, res, e);
		}
	 }
}