Programming Languages 10 lessons 20 quiz questions
Java Core
Master Java core concepts for software engineering interviews, covering OOP, collections, streams, concurrency, JVM internals, and common interview patterns.
What You Will Learn
- ✓ OOP Fundamentals — Classes, Inheritance, Polymorphism, Interfaces
- ✓ Collections Framework — List, Set, Map, Queue, Choosing the Right Collection
- ✓ Generics & Type Safety — Wildcards, Bounded Types, Type Erasure
- ✓ Exception Handling — Checked vs Unchecked, Custom Exceptions, Best Practices
- ✓ Java 8+ Streams & Lambdas — Functional Interfaces, Stream Pipeline, Collectors
- ✓ Multithreading & Concurrency — Thread, ExecutorService, Synchronization, CompletableFuture
- ✓ JVM Internals & Memory — Heap, Stack, GC, ClassLoader, JIT
- ✓ String Handling & Immutability — String Pool, StringBuilder, intern(), Common Pitfalls
- ✓ I/O & Serialization — Streams, NIO, Files API, Object Serialization
- ✓ Common Interview Patterns — equals/hashCode, Comparable, Immutable Classes, Builder Pattern
Overview
Master Java core concepts for software engineering interviews, covering OOP, collections, streams, concurrency, JVM internals, and common interview patterns.
Java OOP rests on four pillars: encapsulation, inheritance, polymorphism, abstraction.
Key: abstract class provides partial implementation; interface defines a contract. A class can implement multiple interfaces but extend only one class.
Python Implementation
Sample Quiz Questions
1. What is the output of: String a = "hello"; String b = "hello"; System.out.println(a == b);
· Difficulty: /5
2. Which collection provides O(1) average-case time for get(), put(), and containsKey()?
· Difficulty: /5
3. What happens when you call stream() operations without a terminal operation?
· Difficulty: /5
+ 17 more questions available in the full app.
Related Topics
Master Java Core for Your Next Interview
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