7-Day Java Interview Preparation Plan
Your saved questions plus a day-by-day plan. Add questions with Save to → 7-Day Job Prep on any question page.
Day-by-day plan
Day 1Java basics and JVM
- Revise JDK, JRE, JVM, memory areas and garbage collectors
- Practise 10 basic programs: prime, palindrome, reverse, Fibonacci
- Write short answers on == versus equals and static versus instance
- Review Java 8 to 21 feature list
Day 2OOP and design
- Explain the four pillars with your own project examples
- Code equals and hashCode, an immutable class and a builder
- Revise SOLID and singleton, factory and strategy patterns
- Prepare answers on abstract class versus interface
Day 3Strings and exceptions
- Solve 8 string problems: anagram, first unique character, longest substring
- Revise checked versus unchecked and try-with-resources
- Write a custom exception with a Spring global handler
- Review string pool and StringBuilder questions
Day 4Collections
- Draw HashMap internals: buckets, hashing, treeification and resize
- Solve 6 problems using HashMap, PriorityQueue and TreeMap
- Implement an LRU cache with LinkedHashMap
- Revise fail-fast iterators and ConcurrentHashMap
Day 5Multithreading and streams
- Code producer-consumer with BlockingQueue and odd-even printing
- Revise volatile, synchronized, locks and deadlock prevention
- Solve 10 stream problems with groupingBy, partitioningBy and flatMap
- Read about virtual threads and CompletableFuture
Day 6JPA and Spring Boot
- Revise entity states, lazy loading and the N+1 fix
- Explain @Transactional pitfalls and isolation levels
- Walk through your Spring Boot project: layers, security and tests
- Prepare microservice answers on circuit breaker, saga and Kafka
Day 7Mock interview and HR
- Take a timed mock coding round with two medium problems
- Practise a 2 minute project explanation aloud
- Prepare STAR stories for a bug fix, a deadline and a conflict
- Revise the 30 key points and rest well
Frequently asked questions
Can I prepare for a Java interview in 7 days?
Seven days is enough to revise and sharpen, not to learn from zero. Use the plan to cover each core topic once, practise questions daily and finish with a mock interview.
How do I add questions to the plan?
On any question page choose Save to → 7-Day Job Prep. Saved questions show up at the top of this page.
How many hours a day should I study?
Two to four focused hours a day works for most people: one hour of revision, one to two hours of questions, and the rest on projects or mock answers.
Questions to practise each day
Company-wise Java questionsExperience-wise Java questionsRole-wise Java questionsCity-wise Java questionsMost asked Java questionsScenario-based questionsPractical / hands-on questionsHR & behavioural questionsJava mock interviewOnline assessment questionsTechnical round questionsManagerial round questionsJava topic sheets