How can I fetch data from facebook using a query string in salesforce?

How can I fetch data from fa开发者_JS百科cebook using a query string in salesforce?

This is what I have:

I am not fetching data so what can I do?

Have you called Http's send method after this?. I guess you have but are not getting any response back?

Any external site you call from Apex must be registered in the Remote Site Settings. Make sure to add Facebook's URL under Admin Setup > Security Controls > Remote Site Settings