Mine

public void putHeader(String mtbl,String value){
		header.put( mtbl, value); //// ayth einai mia typou response method pou orizw se mia klash named Response

Response resp= new Response(HTTP_OK,mime,file);
		resp.putHeader("Content-length",stringlenth); kai apou kaaapou telospantwn thn kalw.. to stringlenth einai ayto pou kaname string prin..
kai bgazei null pointer exception sth xrisi tis method