If you get this compilation error, it means that you have not included the servlet jar in the classpath. The correct way to include this jar is to add the Server Runtime jar to your eclipse project. You should follow the steps below to address this issue:
You can download the servlet-api.jar from here
http://www.java2s.com/Code/Jar/s/Downloadservletapijar.htm
Save it in directory. Right click on project -> go to properties->Buildpath and follow the steps.
Note: The jar which are shown in the screen are not correct jar.
you can follow the step to configure.
