jsp 图书管理网站

package Servlet; import JavaBean.BookInf; import JavaBean.DBbean; import java.io.IOException; import java.io.PrintStream; import java.sql.ResultSet; import java.sql.SQLException; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.*; public class Book_Insert extends HttpServlet { public Book_Insert() { } public void doGet(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse) throws ServletException, IOException { javax.servlet.http.HttpSession httpsession = httpservletrequest.getSession(); String s = "/Book_Manage.jsp"; BookInf bookinf = new BookInf(); httpservletrequest.setCharacterEncoding("gb2312"); String s1 = httpservletrequest.getParameter("id").trim(); String s2 = httpservletrequest.getParameter("name").trim(); String s3 = httpservletrequest.getParameter("author").trim(); String s4 = httpservletrequest.getParameter("pubhouse").trim(); String s5 = httpservletrequest.getParameter("type").trim(); String s6 = httpservletrequest.getParameter("price").trim(); String s7 = httpservletrequest.getParameter("ifNew").trim(); DBbean dbclass = new DBbean(); if(s1.equals("")) { bookinf.setId("*\u672C\u9879\u5FC5\u987B\u586B\u5199!"); s = "/Book_Insert.jsp"; } else if(isExist(s1)) { bookinf.setId("*\u4E0E\u5176\u5B83\u56FE\u4E66\u7684ID\u51B2\u7A81\uFF01"); s = "/Book_Insert.jsp"; } if(s2.equals("")) { bookinf.setName("*\u672C\u9879\u5FC5\u987B\u586B\u5199!"); s = "/Book_Insert.jsp"; } if(s3.equals("")) { bookinf.setAuthor("*\u672C\u9879\u5FC5\u987B\u586B\u5199!"); s = "/Book_Insert.jsp"; } if(s4.equals("")) { bookinf.setPubhouse("*\u672C\u9879\u5FC5\u987B\u586B\u5199!"); s = "/Book_Insert.jsp"; } if(s5.equals("0")) { bookinf.setType("*\u672C\u9879\u5FC5\u987B\u586B\u5199!"); s = "/Book_Insert.jsp"; } if(s6.equals("")) { bookinf.setPrice("*\u672C\u9879\u5FC5\u987B\u586B\u5199!"); s = "/Book_Insert.jsp"; } if(s.equals("/Book_Manage.jsp")) { String s8 = (new StringBuilder()).append("insert into book values('").append(s1).append("'").append(",").append("'").append(s2).append("'").append(",").append("'").append(s3).append("'").append(",").append("'").append(s4).append("'").append(",").append("'").append(s5).append("'").append(",").append("'").append(s7).append("'").append(",").append("'").append(s6).append("'").append(")").toString(); dbclass.connect(); dbclass.executeUpdate(s8); dbclass.closeConnection(); } httpservletrequest.setAttribute("errInf", bookinf); RequestDispatcher requestdispatcher = httpservletrequest.getRequestDispatcher(s); requestdispatcher.forward(httpservletrequest, httpservletresponse); } public void doPost(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse) throws ServletException, IOException { doGet(httpservletrequest, httpservletresponse); } public boolean isExist(String s) { boolean flag = false; String s1 = (new StringBuilder()).append("select * from book where b_id='").append(s).append("'").toString(); DBbean dbclass = new DBbean(); dbclass.connect(); ResultSet resultset = dbclass.executeQuery(s1); try { if(resultset.next()) flag = true; } catch(SQLException sqlexception) { System.err.println((new StringBuilder()).append("Erro with connection:").append(sqlexception).toString()); } dbclass.closeConnection(); return flag; } }