This is small and quick blog on an issue I faced today. I was working on Cordova android project and I updated my Java version and JRE and suddenly I got following error after clean and re building entire work space.
The project cannot be built until build path errors are resolved.
I tried several solutions as usual like removing JAR file references and re add them. Quit eclipse and restart it etc. Still the problem persists. So as all software engineer do, I tried to search on Google and Stackoverflow and find out the same solutions which I already tried. I kept looking for some time and quick applying solutions again and again but this error does not go away. So finally I decided to take backup my current project and start making changes in other copy.
Tried so many things and did refresh workspace so many times. Did clean and rebuild entire workspace but it wasn't working. Finally I solved it by following step.
1) Go to project explorer and right click on project
2) Select properties.
3) On left side choose Project References.
Once you select this on left, right side you will get your project references with check marks on left side. If you see them un checked as show in following screenshot.