How to Fetch Records From Database Using Servlet in Java

Sandeep Sharma
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Introduction

This article explains how to fetch data from a database using a Servlet in Java. The NetBeans IDE is used for this application.

Fetch Data from Database

This article explains how to fetch data from a database using a servlet in Java. For this application we need the following tools:

Oracle10g Database
Tomcat Server
NetBeans IDE

We need to create the following files:

userlogin table
index.html file
FetchData.java file
web.xml file

1. userlogin table

For fetching data you need to have a table with multiple records. In this application I use a "userlogin" table syntax for creating this table as in the following:

create table userlogin(name varchar2(4000), password varchar2(4000), emailid varchar2(4000), country varchar2(4000));

To insert data the syntax is:

insert into userlogin values ('', '', '', '');

For example I inserted two rows using:

insert into userlogin values ('Sandeep', 'sandeep', '[email protected]', 'India');

insert into userlogin values ('Rahul', 'rahul', '[email protected]', 'India');

For creating manually

To manually create a table use the following link in which I show a demo.

http://www.c-sharpcorner.com/UploadFile/fd0172/registration-form-using-servlet-in-java/

Creating other files

We need to use the following procedure to create the other files.

Step 1

Open the NetBeans IDE.

Step 2

Choose "Java web" -> "Web application" as in the following:

Step 3

Type your project name as "Welcome" and click on "Finish" as in the following:

Step 4

Now delete your default "index.jsp" file and create a new "index.html" file and write the following code there.

index.html

<!DOCTYPE html>

<html>

<head>

<title>TODO supply a title</title>

</head>

<body>

Enter your Name: <input type="text" name="uname"/><br/>

</form>

</body>

</html>

Step 5

Now create a servlet file with the name "Search" and write the following code there.

Search.java

import java.io.*;

import java.sql.*;

import javax.servlet.ServletException;

import javax.servlet.http.*;

public class Search extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

response.setContentType("text/html");

PrintWriter out = response.getWriter();

String name=request.getParameter("uname");

try{

Class.forName("oracle.jdbc.driver.OracleDriver");

Connection con=DriverManager.getConnection("jdbc:oracle:thin:@mcndesktop07:1521:xe","sandeep","welcome");

PreparedStatement ps=con.prepareStatement("select * from userlogin where name=?");

ps.setString(1,name);

out.print("<table width=25% border=1>");

out.print("<center><h1>Result:</h1></center>");

ResultSet rs=ps.executeQuery();

/* Printing column names */

ResultSetMetaData rsmd=rs.getMetaData();

while(rs.next())

{

out.print("<tr>");

out.print("<td>"+rsmd.getColumnName(1)+"</td>");

out.print("<td>"+rs.getString(1)+"</td></tr>");

out.print("<tr><td>"+rsmd.getColumnName(2)+"</td>");

out.print("<td>"+rs.getString(2)+"</td></tr>");

out.print("<tr><td>"+rsmd.getColumnName(3)+"</td>");

out.print("<td>"+rs.getString(3)+"</td></tr>");

out.print("<tr><td>"+rsmd.getColumnName(4)+"</td>");

out.print("<td>"+rs.getString(4)+"</td></tr>");

}

out.print("</table>");

}catch (Exception e2)

{

e2.printStackTrace();

}

finally{out.close();

}

Step 6

Check your default web.xml file that it has the same code as in the following:

web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">

<servlet-name>Search</servlet-name>

<servlet-class>Search</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>Search</servlet-name>

<url-pattern>/Search</url-pattern>

</servlet-mapping>

</web-app>

Step 7

Now our project is ready to run. Right-click on the "Project" menu then select "Run" as in the following:

Step 8

The following output is generated.

Step 9

Now type the name as you pass in your database file. For example I passed the name "Sandeep" since it exists in my database.

Step 10

Now click on the "Search" button. The data from the database is fetched with the username Sandeep as in the following:

Step 11

Now click on the back button of the browser and provide another name. Since I have two records in the database I passed the other one as the name "Rahul".