To resolve the issue delete .lock file under  workspace/.metadata/ and re-import the project using below steps

Inside package explorer, right click -> import -> General -> Existing Projects into Workspace -> next -> find your project in "Select root directory" -> Finish

Also you can  re-created workspace and imported projects again.Creating a new workspace is done via:

File > Switch Workspace

Abhishek Tiwari
edureka! Support Team
On Sat, 9 Apr at 8:38 AM , Sid23.vyas <> wrote:
Cannot determine URI for "/Sidhu/src/".
my whole java project is deleted why this thing has happened