There is an assignment typically given to all the candidates and the candidates are expected to complete the assignment, which should be a working prototype within a week. They do provide extension to complete the assignment if required.

It was telephonic discussion. one junior guy interviewed me, he asked basic questions like HashTable Vs HashMap. concurrent hashmap, volatile. very easier one. but weired thing is, they are still asking these questions to Technical Architect? After discussion, i asked HR for feedback, no response. Advice to Hiring manager, if you are interviewing senior candidates, please ask question up to that level.