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

import library.DBConnection;


public class XujieController extends Controller {
	 public void doPost (HttpServletRequest req,
				HttpServletResponse res) throws ServletException, IOException {
		HttpSession session = req.getSession();
		//req.setCharacterEncoding("GB2312"); 
		
		String id =  new String(req.getParameter("id").getBytes("ISO-8859-1"),"GB2312");
		String bookid = new String(req.getParameter("bookid").getBytes("ISO-8859-1"),"GB2312");
		int time = Integer.parseInt( new String(req.getParameter("time").getBytes("ISO-8859-1"),"GB2312"));
		session = req.getSession();
	
		boolean change = true;
	    if(time<=0){
	    	change = false;
	    }
		try {
		    if(change == false){	
			    res.sendRedirect("../brbookdetail.jsp?jieguo=failed1&id="+id);
		    }else{
			    String url ="jdbc:mysql://localhost/library?user=root&password=linux&useUnicode=true&characterEncoding=GB2312" ;
			    Connection conn= DriverManager.getConnection(url); 
			    Statement stmt=conn.createStatement();
			   
			    String sql = "update bookhavebr set xujie=xujie-1 ,reDATA= DATE_ADD(reDATA, Interval 1 month) where findid = '"+bookid+"'";
			    boolean rs=stmt.execute(sql);
			    res.sendRedirect("../brbookdetail.jsp?jieguo=success&id="+id);	
			  // res.sendRedirect("../test.jsp?jieguo="+sql);	
		    }
		} catch (Exception e2) {
			sendErrorRedirect(req, res, e2);
		}
	    }
}