JAVA-Daily-Tasks

Day 13 - Collections

Introduction

Day 13 focuses on the Java Collections Framework.

The practice programs cover commonly used collection classes and concepts such as ArrayList, LinkedList, HashSet, TreeSet, HashMap, TreeMap, Iterator, sorting, and removing duplicate values.

Objectives

Understand the Java Collections Framework
Learn how to use ArrayList
Learn how to use LinkedList
Understand HashSet
Understand TreeSet
Learn key-value pairs using HashMap
Learn sorted key-value pairs using TreeMap
Use Iterator to traverse collections
Sort collection elements
Remove duplicate values using collections

Topics Covered

ArrayList
ArrayList with User Input
LinkedList
HashSet
TreeSet
HashMap
TreeMap
Iterator
Collection Sorting
Removing Duplicates

Folder Structure

Day-13-Collections/
│
├── Questions/
│   └── Questions.txt
│
├── Solutions/
│   ├── Q01_ArrayList.java
│   ├── Q02_ArrayList_User_Input.java
│   ├── Q03_LinkedList.java
│   ├── Q04_HashSet.java
│   ├── Q05_TreeSet.java
│   ├── Q06_HashMap.java
│   ├── Q07_TreeMap.java
│   ├── Q08_Iterator.java
│   ├── Q09_Sort_Collection.java
│   └── Q10_Remove_Duplicates.java
│
├── Screenshots/
│   ├── Output_1.png
│   ├── Output_2.png
│   ├── Output_3.png
│   ├── Output_4.png
│   ├── Output_5.png
│   ├── Output_6.png
│   ├── Output_7.png
│   ├── Output_8.png
│   ├── Output_9.png
│   └── Output_10.png
│
└── README.md

Practice Questions

Q01 - ArrayList

Create an ArrayList of names, add 5 names, and display all the names.

Solution: Q01_ArrayList.java

Output

Q01 Output

Q02 - ArrayList with User Input

Get 5 numbers from the user, store them in an ArrayList, and calculate their sum.

Solution: Q02_ArrayList_User_Input.java

Output

Q02 Output

Q03 - LinkedList

Create a LinkedList of fruits, add fruits, remove one fruit, and display the remaining fruits.

Solution: Q03_LinkedList.java

Output

Q03 Output

Q04 - HashSet

Create a HashSet containing duplicate numbers and observe that duplicate values are removed.

Solution: Q04_HashSet.java

Output

Q04 Output

Q05 - TreeSet

Create a TreeSet containing numbers and display them in sorted order.

Solution: Q05_TreeSet.java

Output

Q05 Output

Q06 - HashMap

Create a HashMap containing student names and marks and display all key-value pairs.

Solution: Q06_HashMap.java

Output

Q06 Output

Q07 - TreeMap

Create a TreeMap containing employee IDs and names and display the entries in sorted key order.

Solution: Q07_TreeMap.java

Output

Q07 Output

Q08 - Iterator

Create an ArrayList of names and use Iterator to display each name.

Solution: Q08_Iterator.java

Output

Q08 Output

Q09 - Sort Collection

Create an ArrayList of numbers and sort the numbers in ascending order.

Solution: Q09_Sort_Collection.java

Output

Q09 Output

Q10 - Remove Duplicates

Create an ArrayList containing duplicate numbers and remove the duplicate values using a collection.

Solution: Q10_Remove_Duplicates.java

Output

Q10 Output

How to Compile and Run

Open PowerShell and navigate to the Solutions folder:

cd "C:\Disk D\Full Stack fol\JAVA-Daily-Tasks\Day-13-Collections\Solutions"

Compile all Java programs:

javac *.java

Run the programs individually:

java Q01_ArrayList
java Q02_ArrayList_User_Input
java Q03_LinkedList
java Q04_HashSet
java Q05_TreeSet
java Q06_HashMap
java Q07_TreeMap
java Q08_Iterator
java Q09_Sort_Collection
java Q10_Remove_Duplicates

Solutions

No.	Topic	Solution
Q01	ArrayList	`Q01_ArrayList.java`
Q02	ArrayList with User Input	`Q02_ArrayList_User_Input.java`
Q03	LinkedList	`Q03_LinkedList.java`
Q04	HashSet	`Q04_HashSet.java`
Q05	TreeSet	`Q05_TreeSet.java`
Q06	HashMap	`Q06_HashMap.java`
Q07	TreeMap	`Q07_TreeMap.java`
Q08	Iterator	`Q08_Iterator.java`
Q09	Sort Collection	`Q09_Sort_Collection.java`
Q10	Remove Duplicates	`Q10_Remove_Duplicates.java`

Key Learning

Through these programs, I practiced:

Creating and managing collections
Adding and removing elements
Using ArrayList
Using LinkedList
Removing duplicates with HashSet
Sorting elements using TreeSet
Storing key-value pairs using HashMap
Sorting keys using TreeMap
Traversing collections using Iterator
Sorting collections using Collections.sort()

Technologies Used

Java
VS Code
Git
GitHub

Progress

Day	Topic	Status
Day 01	Java Basics	Completed
Day 02	Conditional Statements	Completed
Day 03	Real-World Conditions	Completed
Day 04	Loops	Completed
Day 05	Number Programs	Completed
Day 06	Pattern Programs	Completed
Day 07	Arrays Basics	Completed
Day 08	Arrays Problem Solving	Completed
Day 09	String Basics	Completed
Day 10	Methods	Completed
Day 11	OOP Basics	Completed
Day 12	OOP Advanced	Completed
Day 13	Collections	Completed

Learning Goal

The goal of this daily Java practice is to strengthen Java fundamentals, Object-Oriented Programming concepts, Collections, logical thinking, problem-solving skills, and technical interview preparation.

Status

Day 13 - Collections Completed ✅

Next: Day 14 - Exception & File Handling