java 
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import javax.servlet.*; 
import javax.servlet.http.*; 
import java.io.IOException; 
import java.io.PrintWriter; 
public class HelloServlet extends HttpServlet { 
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, 
IOException { 
PrintWriter out = response.getWriter(); 
out.println("Hello from HttpServlet!"); 
} 
} 
Step 1: Install Apache Tomcat 
Download and install Apache Tomcat. 
Set up Tomcat by configuring environment variables (CATALINA_HOME and JAVA_HOME), if needed. 
Step 2: Save and Structure Your Servlet 
Save the servlet code in a file named HelloServlet.java. 
Organize it within the WEB-INF/classes directory inside your web application folder. For example: 
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your-webapp 
├── WEB-INF 
│   ├── classes 
│   │   └── HelloServlet.java 
│   └── web.xml 
Step 3: Compile the Servlet 
Open a terminal or command prompt, navigate to WEB-INF/classes, and compile: 
bash 
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javac -classpath <path-to-servlet-api.jar> HelloServlet.java 
Replace <path-to-servlet-api.jar> with the path to servlet-api.jar in the lib folder of your Tomcat installation. 
Step 4: Configure web.xml 
In the WEB-INF folder, create or update web.xml with the servlet mapping: 
xml 
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<web-app> 
<servlet> 
<servlet-name>HelloServlet</servlet-name> 
<servlet-class>HelloServlet</servlet-class> 
</servlet> 
<servlet-mapping> 
<servlet-name>HelloServlet</servlet-name> 
<url-pattern>/hello</url-pattern> 
</servlet-mapping> 
</web-app> 
Step 5: Deploy and Start Tomcat 
Place the your-webapp folder in Tomcat’s webapps directory. 
Start Tomcat by running startup.sh (Linux/Mac) or startup.bat (Windows) in the bin folder. 
Step 6: Access the Servlet 
Open a browser and navigate to: http://localhost:8080/your-webapp/hello 
Expected Output 
If everything is set up correctly, you should see: 
plaintext 
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Hello from HttpServlet!