Infosys java interview questions

  1.  Difference between Serialization and externalization in java ?
  2. How to overide default serialization mechanism in java?
  3. What is the purpose of Serialversion uid and what happens if we don't define this?
  4. Difference between checked and unchecked exceptions in java?
  5. When to use Runnable vs thread in java ?
  6. Difference between process and thread in java ?
  7. what happens when exception occurs in thread ?
  8. Why wait(), notify(), notifyAll() are not defined in thread class ?
  9. Difference between shallow copy and deep copy in java ?
  10. What are types of inner classes in java ?
  11. when do we use inner classes in java ?
  12. How hashmap works in java?
  13. Difference between generic servlet and http servlet ?
  14. How cookies work in session handling?
  15. What is preinitialization of servlet?
  16. How to implement single threaded model in servlet ?
  17. Difference between struts 1 and struts 2 ?
  18. What is OGNL ?
  19. What is value stack ?
  20. Which class is front controller in struts 2 ?
  21. Difference between action and action support in java ?
  22. Difference between Ant and Maven ?
  23. Explain what is maven repository central ?
  24. What are transitive dependencies and how transitive dependencies are handle in maven ?
  25. What is the default location of maven repository ?
  26. Explain spring bean life cycle ?
  27. Explain different spring bean scopes ?
  28. Are singleton beans thread safe ?
  29. Name some design patterns  used in spring ?
  30. What is n + 1 select problem in hibernate ?
  31. Difference between save(), and persist() in hibernate?/
  32. Explain different types of  caches available in hibernate ?
  33. Difference between merge and update in hibernate?