window-> Preferences-> java-> Installed JREs click on your right side and then the Edit jre
Locate the jar rt.jar the end, on the right Source Attachment
Click on the right path you choose External File src resides, and then click ok on it
window-> Preferences-> java-> Installed JREs click on your right side and then the Edit jre
Locate the jar rt.jar the end, on the right Source Attachment
Click on the right path you choose External File src resides, and then click ok on it