I had a similar problem while I was trying to start my tomcat. I would suggest that you check “Classpath” the following way:
1) Run Configurations
- Right click on your project
- then click “Run” -> “Run Configurations…”
- there check your settings for you project (e. g. in my case it was the Apache Tomcat)
- here look into you tab “Classpath” under “User Entries”
2) Project classpath
- Right click on your project -> “Properties” -> “Java Build Path”
- now check the “Source” Tab as well as your “Libraries” Tab
- Problems should be marked red in the “Libraries” tab