addbookcontroller.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;


@SuppressWarnings("serial")
public class AddbookController 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 name = new String(req.getParameter("name").getBytes("ISO-8859-1"),"GB2312");
		String auther = new String(req.getParameter("auther").getBytes("ISO-8859-1"),"GB2312");
		String publisher =new String( req.getParameter("publisher").getBytes("ISO-8859-1"),"GB2312");
		String publishdata = new String(req.getParameter("publishdata").getBytes("ISO-8859-1"),"GB2312");
		String price = new String(req.getParameter("price").getBytes("ISO-8859-1"),"GB2312");
		String ISBN = new String(req.getParameter("isbn").getBytes("ISO-8859-1"),"GB2312");
		String kind = new String(req.getParameter("kind").getBytes("ISO-8859-1"),"GB2312");
		String beizhu = new String(req.getParameter("beizhu").getBytes("ISO-8859-1"),"GB2312");
		
		session = req.getSession();
	
		boolean change = true;
		boolean change1 = true;
		boolean change2 =true;
		try {
			DBConnection connection = DBConnection.Instance();
			String sql = "select * from booktitle where findid ='"+id+"'";
			ResultSet w = null;
			w = connection.runQuery(sql);
			if(w.next()){
				change1 = false;
			}
			
			sql = "select * from books where isbn ='"+ISBN+"'";
			w = connection.runQuery(sql);
			if(w.next()){
				change2 = false;
			}
			
		} catch (Exception e1) {
			 sendErrorRedirect(req, res, e1);
		}
		if(id.equals("")||name.equals("")||auther.equals("")||
				publisher.equals("")||publishdata.equals("")||price.equals("")||ISBN.equals("")||
				kind.equals("")){
			    change= false;
		}
		try {
		    if(change1 == false){	
			    res.sendRedirect("../admin/addbook.jsp?jieguo=failed1");
		    }else if(change==false){
		    	//res.sendRedirect("../test.jsp?jieguo="+"update reader set password = '"+newpasswd+"' where ReaderID='" +(String)session.getAttribute("readerno")+ "'");
		    	res.sendRedirect("../admin/addbook.jsp?jieguo=failed2");
		    }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 ="";
			    if(change2==false){
			    	sql = "update books set isinno = isinno+1 where isbn = '"+ISBN+"'";
			    }else{
			    	 sql = "insert into books (isbn,name,auther,publisher,publdata,price,isinno,beizhu,kind) " +
			    		" values ('"+ISBN+"','"+name+"','"+auther+"','"+publisher+"','"+publishdata+"',"+price+",1,'"
			            +beizhu+"','"+kind+"')";
			    }
			    boolean rs=stmt.execute(sql);
			    sql = "insert into booktitle (findid,isbn,isin) values ('"+id+"','"+ISBN+"','yes')";
				 // res.sendRedirect("../test.jsp?jieguo="+sql);
			   rs=stmt.execute(sql);
			    res.sendRedirect("../admin/addbook.jsp?jieguo=success");	
			  // res.sendRedirect("../test.jsp?jieguo="+sql);	
		    }
		} catch (Exception e2) {
			sendErrorRedirect(req, res, e2);
		}
	    }
}