Core Java: ========= 1. Why String is immutable ? 2. How HashMap works internally ? 3. OOPS concepts and Polymorphism with example ? 4. Thread creation, Diff between Sleep and Wait ? 5. Synchronization and Serializable ? 6. Collections which you have used in your project and difference between them ? 7. String pooling concepts and diff between String created with New keyword and Literal ? 8. How many ways an object can be created in Java ? 9. Exceptions handling basic questions. Spring & Hibernate =============== 1. What is IOC and DI ? 2. Annotations which you have used. 3 . Autowiring. 4. Stereotype annotations. 5. Spring JDBC vrs Hibernate. 6. Class to Table mapping using JPA annotations. 7. Hibernate configurations. 8. Different types of Spring container. 9. Spring JPA configurations. 10. Spring Hibernate integration. 11. Spring security worked or not ? If yes how to configure and how it works ? Web Services =========== 1. Different between rest and soap ? 2. Protocol used by REST ? 3. Different HTTP methods supported by REST. 4. Annotations in JAX-RS like produces consumes ? 5. Which implementation of JAX-RS is used like Jersey or Spring With REST ? Extra ==== 1. How to deploy code in WAS or Jboss ? 2. How to configure JOB in jenkins ? 3. What is docker ? 4. Have you worked with AWS or Azure ?