SAP Developer interview questions

Internals of JAVA Collections

Questions were from all computer fields. But more questions were from database and data structure. They asked linked list, doubly linked list, circularly linked list from data structure. Along with these they asked other programs using recursion like reversing a linked list using recursion. Normalization, joins and SQL queries were asked in databases. Algorithm efficiency using Big Oh notation was asked in online test. They didn't ask any puzzle to me during the interview but they asked it to my friends. They asked to explain why java is platform independent.