Debug : javax.servlet.http.httpservletrequest cannot be resolved

You can do either of the following to resolve this error.

• Right-click the project tab, click Properties.
• Choose Build Path -> Java Build Path
• Choose Add External JARs
• Browse to find and select servlet-api.jar which should be present in ...\apache-tomcat-7.0.61\lib\
• Click OK to update the build path.

OR
you can simply copy the servlet-api.jar present in  ...\apache-tomcat-7.0.61\lib\ and copy that jar files into lib folder, which is in WEB-INF. then just clean and built your project, your errors will be solved.

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