Create dynamic page through JSP
This is detailed jsp code that shows how to create dynamic page. This code shows one by one record of student from database on click a button named 'next record'. On each click of button, application fetch next record from database.
Create a database : Before running this jsp code, first create a database named 'student' through the sql query given below in mysql command prompt :-
| mysql> create database student; |
Then create a table named 'stu_info' in the same database through following sql query :-
| create table stu_info ( ID int not null auto_increment, Name varchar(20), Address varchar(20), Phone varchar(15), primary key(ID) ); |
Create your application directory named "user" in the Tomcat server. Before running this java code you need mysql connector jar in the Tomcat-6.0.16/webapps/user/WEB-INF/lib.
ConnectJspToMysql.jsp:
This file provides full code how to connect with database and showing the next record of database in JSP.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<%@ page import="java.sql.*" %>
<%@ page import="java.io.*" %>
<HTML>
<HEAD>
<TITLE>Navigating in a Database Table </TITLE>
</HEAD>
<BODY bgcolor="#ffffcc">
<font size="+3" color="green"><br>Welcome in www.roseindia.net !</font>
<br>
<font size="+1" color="#6E6E6E"><br>This is dynamic page that shows data<br>
from database as per user choice.</font>
<% int current = 0;
// declare a connection by using Connection interface
Connection connection = null;
/* Create string of connection url within specified format with machine
name, port number and database name. Here machine name id localhost
and database name is student. */
String connectionURL = "jdbc:mysql://localhost:3306/student";
/*declare a resultSet that works as a table resulted by execute a specified
sql query. */
ResultSet rs = null;
%>
<FORM NAME="form1" ACTION="ConnectJspToMysql.jsp" METHOD="get"><%
if (request.getParameter("hidden") != null) {
current = Integer.parseInt(request.getParameter("hidden"));
}
// Declare statement.
Statement statement = null;
try {
// Load JDBC driver "com.mysql.jdbc.Driver"
Class.forName("com.mysql.jdbc.Driver").newInstance();
/* Create a connection by using getConnection() method that takes
parameters of string type connection url, user name and password to
connect to database. */
connection = DriverManager.getConnection(connectionURL, "root", "root");
/* createStatement() is used for create statement object that is
used for sending sql statements to the specified database. */
statement = connection.createStatement();
// executeQuery() method execute specified sql query.
rs = statement.executeQuery("select * from stu_info");
for (int i = 0; i < current; i++) {
rs.next();
}
if (!rs.next()) {
%>
<FONT size="+2" color="red"></b>
<%
out.println("Sorry ! found some problems with database.");
} else {
%>
<TABLE style="background-color: #ECE5B6;" WIDTH="30%" >
<TR><TH width="50%">ID</TH><TD width="50%"> <%= rs.getInt(1)%> </TD></tr>
<TR><TH>Name</TH><TD> <%= rs.getString(2)%> </TD></tr>
<TR><TH>City</TH><TD> <%= rs.getString(3)%> </TD></tr>
<TR><TH>Phone</TH><TD> <%= rs.getString(4)%> </TD></tr>
</TR>
</TABLE>
<BR>
<INPUT TYPE="hidden" NAME="hidden" VALUE="<%=current + 1%>">
<INPUT TYPE="submit" VALUE="next record">
</FORM>
<%
}
}
catch (Exception ex) {
%>
<FONT size="+3" color="red"></b>
<%
out.println("Unable to connect to database.");
} finally {
// close all the connections.
rs.close();
statement.close();
connection.close();
}
%>
</FONT>
</FORM>
</body>
</html>
Save this code as a .jsp file named "ConnectJspToMysql.jsp" in the directory Tomcat-6.0.16/webapps/user/ and run this jsp page with following url in address bar of the browser "http://localhost:8080/user/ConnectJspToMysql.jsp".
When click on button, application control goes to database and check for the next record. If next record is found in table, it is shown in browser else an error message.
Error message page:
