What is HashMap in Java — Explained with examples.

Index

  1. What is HashMap in Java?
  2. Initialization of HashMap in Java
  3. Hierarchy of HashMap
  4. Internal Structure of HashMap
  5. Basic Operations of HashMap — Adding Elements, Changing Elements, Removing Elements, Iterating over HashMap
  6. Different methods of HashMap
  7. Factors affecting the performance of HashMap — Initial Capacity, Load Factor, Threshold
  8. Types of Constructors in HashMap
  9. Sorting in HashMap
  10. Summarizing
  11. Conclusion

What is HashMap in Java?

Initialization of HashMap in Java

HashMap<K, V> numbers = new HashMap<K, V>();
HashMap<String, Integer> numbers = new HashMap<String Integer>();

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Ateev Duggal

Ateev Duggal

I am a front-end developer from India with over one year of experience in freelancing with skills like Git, HTML5, CSS3, Bootstrap 4&5, and React.