Tinalu,
Sanity check; did you create a Java project? How/where did you set the src and bin folder?
Does your project have any compilation errors? You will see a red cross somewhere in the Project tree (in the Package Explorer view) if there is a problem, check the Problems view to follow it up.
Eclipse uses an Incremental Builder, is Project > Build Automatically checked?
Can you right click on the project and choose Properties, in the Info page, see the Location value – your bin folder will usually be under that folder, can you see the class files there?
Give the Eclipse help a shot, it’s pretty good – Help > Help Contents > Java Development User Guide.
Best,
Brian.