closepage.java

JAVA邮件系统

/* 
 *
 */

import java.io.*;
import java.text.*;
import java.sql.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

/**
 * @author lizhaoshan
 */

public class ClosePage extends HttpServlet {


    public void doGet(HttpServletRequest request,
                      HttpServletResponse response)
        throws IOException, ServletException
    {
		HtmlOut htmlOut = new HtmlOut (response);

		// 得到名字和口令
		String name,pass;

		Person person = new Person();
		person.setName (CommonMethods.GetUserName(request));
		pass = CommonMethods.GetUserPass (request);
		if( person.getName ()==null || (!person.checkPassword(pass)) )
		{
	    	htmlOut.setErrorID (htmlOut.SHOW_SIMPLE_MESSAGE ,"",
								"请先登录！","Login?action=reLog");
			htmlOut.outHtml();
			return;
		}
	
		String sPage = request.getParameter ("p");
		int nPage=0;
		if( sPage!=null ){
			try{
				nPage = Integer.valueOf (sPage).intValue ();
			}catch(Exception e){
			}
		}
			
		DBOperater DB = new DBOperater ("userchannel");
		String queryString;
		//delete this page 
		queryString = "delete from userchannel where ( username='"
					+ CommonMethods.DealWithSQLParameter (person.getName())
					+ "' and pagenumber="+nPage +")";
		DB.executeUpdate (queryString);
		//update other page;
		queryString = "update userchannel set pagenumber = userchannel.pagenumber-1 where ( username='"
					+ CommonMethods.DealWithSQLParameter (person.getName())
					+ "' and pagenumber>"+nPage+")";
		DB.executeUpdate (queryString);
		queryString = "update person set pagenum = person.pagenum-1 where ( username='"
					+ CommonMethods.DealWithSQLParameter (person.getName())
					+ "' and pagenum > 0"+")";
		DB.executeUpdate (queryString);
		DB.close ();
																				 
		htmlOut.setRedirect ("Login?p="+nPage);
		htmlOut.outHtml ();
    }
}