Synechron Java Tech Lead interview questions

Tech round 1 - ‌Garbage collection and it's methods ‌Classloaders in Java & it's types ‌Diamond problem in Java ‌Why string is immutable ‌intern method in java ‌equals and hashcode ‌how java is platform independent ‌What methods are there in Object class ‌differance between ArrayList and Linked List ‌Internal working of Hashmap ‌Print Hierarchy in an organization ‌Synchronization ‌Serializable and it's usage ‌multithreading - Race condition ‌Streams in Java8 ‌add numbers using streams ‌IOC ‌DI ‌lifecyle of a bean ‌Types of Autowiring ‌@SpringbootApplication annotation ‌Eureka ‌Rest template methods for post ‌ ‌Tech Round 2 ‌ ‌how to create immutable class ‌stop child thread from parent ‌abstraction ‌solid principales Followed by telephonic client round(Citi bank) Followed by HR round

Had three interviews screening, technical interview, HR round. Everything went well and I was told that you have passed all rounds but no offer till date. I was assured that you will receive offer in next week but no response. Overall interview was of average difficulty.