Hi,
Is it possible to create a jar file (mobile app) from JSP files? I mean instead of using some toolkit to compile the java files and create the jar file, can I do the same using JSP files?
Thanks.

in theory. But you should never use a JSP for anything except showing things, NEVER do business logic in them.

in theory. But you should never use a JSP for anything except showing things, NEVER do business logic in them.

Why is it not good to do business logic using JSP files?

Also what will I need to set up the environment to create jar files via JSP? What do I need to install?

How do you find this sort of code? Easy to read? Do you have problems to find out where scriplet starts and where is end? How would you handle methods calls that are so easily available to you through server side coding?

<%@ page language="java" import="java.sql.*" %>

<%
	String driver = "org.gjt.mm.mysql.Driver";
	Class.forName(driver).newInstance();
	

	Connection con=null;
	ResultSet rst=null;
	Statement stmt=null;
	

	try{
		String url="jdbc:mysql://localhost/books?user=
<user>&password=<password>";
		con=DriverManager.getConnection(url);
		stmt=con.createStatement();
	}
	catch(Exception e){
		System.out.println(e.getMessage());
	}

	if(request.getParameter("action") != null){ 
		String bookname=request.getParameter("bookname");
		String author=request.getParameter("author");
		stmt.executeUpdate("insert into books_details(book_name,
author) values('"+bookname+"','"+author+"')");
		rst=stmt.executeQuery("select * from books_details");
		%>
		<html>
		<body>
		<center>
			<h2>Books List</h2>
			<table border="1" cellspacing="0" cellpadding
="0">
			<tr>
				<td><b>S.No</b></td>
				<td><b>Book Name</b></td>
				<td><b>Author</.b></td>
			</tr>
			 	<%
				int no=1;
				while(rst.next()){
				%>
				<tr>
				  <td><%=no%></td>
				  <td><%=rst.getString("
book_name")%></td>
				  <td> <%=rst.getString("author")
%> </td>
				</tr>
				<%
				no++;
	}
	rst.close();
	stmt.close();
	con.close();
%>
			</table>
			</center>
		</body>
	</html>
<%}else{%>
	<html>
	<head>
		<title>Book Entry FormDocument</title>
		<script language="javascript">
		    function validate(objForm){
			if(objForm.bookname.value.length==0){
			alert("Please enter Book Name!");
			objForm.bookname.focus();
			return false;
			}
			if(objForm.author.value.length==0){
			alert("Please enter Author name!");
			objForm.author.focus();
			return false;
			}
			return true;
				}
			</script>
		</head>
		

		<body>
			<center>
<form action="BookEntryForm.jsp" method="post" 
name="entry" onSubmit="return
 validate(this)">
	<input type="hidden" value="list" name="action">
	<table border="1" cellpadding="0" cellspacing="0">
	<tr>
		<td>
			<table>
				<tr>
				<td colspan="2" align="center">
<h2>Book Entry Form</h2></td>
				</tr>
				<tr>
				<td colspan="2">&nbsp;</td>
				</tr>
				<tr>
				<td>Book Name:</td>
				<td><input name="bookname" type=
"text" size="50"></td>
				</tr>
				<tr>
				<td>Author:</td><td><input name=
"author" type="text" size="50"></td>
				</tr>
				<tr>
					<td colspan="2" align="center">
<input type="submit" value="Submit"></td>
					</tr>
				</table>
			</td>
		</tr>
	</table>
</form>
			</center>
		</body>
	</html>
<%}%>

Can you imagine that somebody will also add here Java validation of data received from previous page, code for setting up session or other way of forwarding data, plus add code for some redirecting forward to next page or back to login page of login failed?

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