Java Collection Programs – Basic to Advanced

Last Updated : 22 Jun, 2024
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As it cleared from its name itself “Collection” it is a pre-defined collective bunch of classes and Interfaces present in the “Collection Framework” in Java. Their Classes, Interfaces and Methods are frequently used in competitive programming.

This article provides a variety of programs on Java Collections, that are frequently asked in the Technical round in various Software Engineering Interviews including various operations such as reversing, Iteration, binary search, swapping, and splitting on various DS problems etc.

Additionally, you can practice all essential programs related to Java collection and each program comes with a detailed description, Java code, and output. All the Programs/Examples have been thoroughly tested on both Windows and Linux systems.

Java Collection Programs for Practice: Complete List

Here is a complete list of Java Collection programs for practice:

  1. Java Program to Get the Maximum Element From a Vector
  2. Binary Search on Java Vector
  3. Java Program to Get Elements of a LinkedList
  4. LinkedList clear() Method in Java
  5. Convert an Array into Collection in Java
  6. Java Program to Change a Collection to an Array
  7. Java Program to Compare Elements in a Collection
  8. How to Print a Collection in Java?
  9. How to Make a Collection Read-Only in Java?
  10. Java Program to Remove a Specific Element From a Collection
  11. Collections.reverse() Method in Java with Examples
  12. Collections.shuffle() Method in Java with Examples
  13. How to Get a Size of Collection in Java?
  14. How to Iterate HashMap in Java?
  15. How to Use Enumeration to Display Elements of Hashtable in Java?
  16. Hashtable keySet() Method in Java with Examples
  17. Min and Max in a List in Java
  18. How to Find a Sublist in a List in Java?
  19. How to replace an element in a list?
  20. Java Program to Rotate Elements of the List

Also, feel free to check out our Java interview questions collection – it could come in handy!

Conclusion

In this Java practice post, we have explored a variety of Java collection programs that demonstrate the versatility and power of Java’s collection framework. Each program has showcased different aspects of collections, including lists, sets, maps, and their respective functionalities such as sorting, searching, and iterating. By working through these programs, you’ve gained practical insights into how to manipulate data efficiently using Java collections.

Java Collections Programs – FAQs

1. What are the most popular collections in Java?

The most popular collections in Java are ArrayList, LinkedList, HashSet, and TreeSet. These collections are all efficient and versatile, and they can be used for a variety of tasks.

2. What questions are asked in Collections interview?

Here are some of the questions that are commonly asked in Collections interviews:

  • What is the Java Collections Framework?
  • What are the different types of collections in the Java Collections Framework?
  • What are the differences between ArrayList, LinkedList, and Vector?
  • What are the different ways to iterate through a collection?
  • How do you search for an element in a collection?
  • How do you sort a collection?
  • What are the different ways to add and remove elements from a collection?
  • What are the performance implications of different collection operations?
  • What are the advantages and disadvantages of using generics with collections?
  • How do you handle concurrent access to collections?
  • What are some common mistakes people make when using collections?

These are just a few of the many questions that you may be asked in a Collections interview. The specific questions that you are asked will vary depending on the level of the position you are applying for and the specific company you are interviewing with.

For more, You can check our complete article here.

3. Should I learn Java Collections?

Yes, Collections are a fundamental part of the Java programming language, and they are used in a wide variety of applications. By learning Collections, you will be able to write more efficient and reusable code.

Here are some of the benefits of learning Java Collections:

  • Efficiency
  • Reusability
  • Modularization
  • Portability


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