Experience in Core Java, Spring, Hibernate, Web Services.
1. Worked on JDK5/JDK7/JDK8 and should know the features and must know java memory model(Eden space, Survivors space, PermGen space, Metaspace) and JVM tuning/performance setting using -xms , -xms etc.
2. Must know the features of JDK8 like lambda expression and its internal conversion and execution, streams – sequential and parallel both, addition of interface and methods in concurrency package, functional interfaces and backward compatibility.
3. Must know how to extract and analyze heap dump and thread dump.
4. Hashing technique, equals and hashcode method and rehashing process
Approach to write own hashcode method
Ask about hashmap, weakhashmap.
5. Must have worked on concurrent package and must know 5-6 design patterns and should have implemented in projects (Proxy, Observer, Adapter, Façade, Prototype etc.) or ask some live examples.
6. Lifecycle of spring bean and corresponding interfaces, scope of beans and aware interfaces.
Dependency injection, circular dependency injection and its resolution
1. Synchronization techniques and concurrent collections
Should know the internal implementation of atleast 3 concurrent collections.
2. Garbage collections and types of garbage collectors, configuration and scenarios which one to use when.
Reflection API and its disadvantage and how to overcome those disadvantages
Total Exp – 6 to 8 years
Location – Gurgaon
