Collections Framework

  1. Collections Framework(Collection Interface)
    1. Array
    2. Collection (Interface) & Collections (Utility class)
    3. Serializable and Clonable and RandomAccess Interfaces
  2. List Interface
    1. ArrayList(Best – Frequent Retrieval & Worst – Insertion or Deletion in middle)
    2. LinkedList(Best – Insertion or Deletion in middle & Worst – Read from Middle)
    3. Vector
    4. Stack extends Vector
    5. ArrayDequeue
    6. Difference between ArrayList and Vector
    7. Difference between ArrayList and LinkedList
  3. Set Interface
    1. HashSet (Best : Search)
      1. LinkedHashSet
    2. SortedSet Interface
      1. NavigableSet Interface extends SortedSet Interface
        1. TreeSet (Comparable and Comparator Interface)
    3. Difference between HashSet, LinkedHashSet and TreeSet
    4. Differences between List and Set
  4. Queue Interface
    1. PriorityQueue
    2. BlockingQueue.
      1. LinkedBlockingQueue
      2. PriorityBlockingQueue
    3. Deque
      1. ArrayDequeue
      2. LinkedList
  5. Map Interface
    1. HashMap Class (Resizing of HashMap – Youtube)
      1. LinkedHashMap extends HashMap (Class)
    2. IdentityHashMap Class
    3. WeakHashMap Class
    4. SortedMap Interface
      1. NavigableMap Interface
        1. TreeMap
    5. Hashtable
    6. Properties extends Hashtable
    7. Difference between HashMap and Hashtable
    8. Difference between HashMap and LinkedHashMap
  6. Enum Collection
    1. EnumSet
    2. EnumMap
  7. Cursors
    1. Enumeration Interface
    2. Iterator Interface
    3. ListIterator Interface
    4. Difference between Enumeration, Iterator and ListIterator
    5. Iterator Vs for in loop
  8. Utility Class
    1. Collections
    2. Arrays

Generics

  1. Why Generics in java?
  2. What is Generic Class
  3. Generic Method
  4. Collections with Generics
  5. Bounded Type Parameter
  6. Unbounded Wildcard
  7. Type Erasure
  8. Difference between ? and T i.e Unbounded Wildcard and T

Concurrent Collections

  1. Need for concurrent Collections
  2. Difference between Traditional and Concurrent Collections
  3. ConcurrentMap
  4. ConcurrentHashMap
  5. HashMap vs ConcurrentHashMap
  6. ConcurrentHashMap vs synchronizedMap() vs Hashtable
  7. CopyOnWriteArrayList
  8. ArrayList vs CopyOnWriteArrayList
  9. CopyOnWriteArrayList vs syncronizedList() vs vector
  10. CopyOnWriteArraySet
  11. CopyOnWriteArraySet vs syncronizedSet()
  12. FailFast vs FailSafe Iterator
  • Proof that normal collection is not Thread safe
  • Why Synchronized Collections like Hashtable, Vector are not up to the mark performance wise
  • What is Mutex in context of Thread
  • Learn Atomic and Volatile

Reference – Concurrent Collections

Concurrent Collection Reference – Youtube

Generics

DataStructures

  1. Stack
  2. Queue
  3. Hashtable
  4. Tree
    • Balaced Tree
    • Red and Black Tree
    • BTree (Binary Tree)
      • Binary Search Tree
    • AVL
Java Collection Framework - An Exclusive Guide on Collection Framework - TechVidvan

Hierarchy of all Collections in Java with its method

Collections Interview Questions

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