Annotation Type WebServlet

Since Servlet 3.0, you can use annotation to declare servlet. You simply add the annotation to a java class; so you don’t need to declare servlet in web.xml anymore.

This annotation is processed by the container at deployment time, and the corresponding servlet made available at the specified URL patterns.

If the name attribute is not defined, the fully qualified name of the class is used.

At least one URL pattern MUST be declared in either the value or urlPattern attribute of the annotation, but not both.

The value attribute is recommended for use when the URL pattern is the only attribute being set, otherwise the urlPattern attribute should be used.

Create New Dynamic Web Project

Step 1.1 Create New Project

Go to File->New->Others… Select Dynamic Web Project under Web category then click Next. Type ServletDemo or whatever name you want in the Project name field.

Step 1.2 Configure Target Runtime

  • Click New Runtime… button under Target Runtime.
  • Select Apache Tomcat v7.0. Click Next.
  • Click Browse button to specify Tomcat Server installation directory. The select the folder then click Ok.
  • Click Installed JREs… button to add/remove or edit JRE definition. Remove existing one; then click Add button to configure new one. Select Standard VM; then click Next. Click Directory button to select the root folder of JDK installation. Select the folder then click Ok. Click Finish.
  • Check the JDK then click Ok.
  • Change JRE to the JDK then click Finish.
  • Click Finish the finish the project creation.

Step 2 Create Servlet Class

Step 2.1 Create a Normal HTTP-based Servlet.

  • Right click to the project or src folder, select New -> Class from the menu.
  • In Java package, enter info.java.tips.servlet.
  • In Class Name, choose any name you want.
  • Click Finish.
  • Add extends HttpServlet to the class.
  • Implement doGet() method.

Step 2.2 Annotate The Servlet With @WebServlet Annotation

Add following annotation to the servlet:

or simply

Step 3 Clean & Build

Clean & build the project to clean old classes file (if any) & force the IDE to recompile java code.

  • Go to Project on menu bar; select Clean…
  • Select Clean all projects (default)
  • Click Ok to proceed clean & build.

Step 4 Configure Tomcat

Select Servers window; in case it’s not there, go to Windows -> Show View-> Others… Select Server -> Servers; then click Ok.

If this is the first time you are creating a server, in the Servers area you will see a link as No servers are available click this link to create a new server. Click the link.

Define a New Server window will be opened, In Select the server type. Select Apache -> Tomcat v7.0 Server. Then click Finish.

Step 5 Deploy The Application

  • Right click to the Tomcat Server select Add and Remove.
  • Move the application (ServletDemo) from Available column to Configured. Then click on Finish to deploy it to tomcat server.

Step 6 Start Tomcat Server

Right click on the tomcat server and choose Start or simply click on the green start icon to start the server.

Step 7 Run The Servlet

We assume that you install tomcat on default port (8080) and project name is ServletDemo. Open web browser and type:

http://localhost:8080/ServletDemo/webServletDemo

or

http://localhost:8080/ServletDemo/webServletDemo2

Output

Note: If you’ve already created a dynamic web project & tomcat server up & running. You can skip step 1 – create new project. And to deploy & run the servlet; follow the below steps:

  • Stop the tomcat server
  • Clean & build the project to re-compile the application
  • Start the tomcat server
  • Open web browser and run the URL.