Project cannot be built until build path errors are resolved eclipse

Question

I am trying to build a Java project. This used to be a breeze for me but ever since I changed my workspace to another location to store my new projects, I've been running into trouble. I get these two errors.

Description Resource    Path    Location    Type
The project cannot be built until build path errors are resolved    InterviewPractice       Unknown Java Problem
Unbound classpath container: 'JRE System Library [JavaSE-1.7]' in project 'InterviewPractice'   InterviewPractice       Build path  Build Path Problem

I've looked up fixes online but none of them seem to be working for me.

While building the project, selecting the JRE selection. I'm also not sure what to choose. I think default it was set to OSGi/minimum 1.0 but I'm honestly not sure what that does. I simply want to build simple programs for interview practice. So JavaSE-1.7?

when I click JRE system library a popup that says An error has occurred. See error log for more details. java.lang.NullPointerException

Answer 1

I think it is about your jre version. Did you try jre6 ?

Package Explorer >> Right Click >> Build Patch >> Configure Build Path >> Libraries >>

Delete Your JRE .

Then Add Library >> JRE System Library >> Environments >> Select JRE6 >> Finish