Java Programming Labs

Your Task: Create a Person class that encapsulates personal data with private fields, a constructor, getters/setters, and a display method.

Detailed Requirements:
1. Create a class named "Person" with private fields:
   � private String name;
   � private int age;

2. Create a constructor that takes name and age parameters and initializes the fields.
   Syntax: public Person(String name, int age) { this.name = name; this.age = age; }

3. Create getter and setter methods for each field:
   � getName(), setName(String name)
   � getAge(), setAge(int age)

4. Create a displayInfo() method that prints the person's details.

5. In main(), create Person objects and call their methods.

OOP Concepts:
� Encapsulation: Private fields protect data; access via methods
� Constructor: Special method to initialize objects
� this keyword: Refers to the current object instance

Expected Output:
Person: Alice, Age: 25 Person: Bob, Age: 30 After birthday: Bob, Age: 31

Your Task: Create an inheritance hierarchy with a base Animal class and derived Dog and Cat classes that override methods.

Detailed Requirements:
1. Create base class "Animal" with:
   � protected String name; (accessible by subclasses)
   � Constructor taking name parameter
   � makeSound() method printing generic sound

2. Create class "Dog" extending Animal:
   � Call parent constructor using super(name)
   � @Override makeSound() to print "Woof!"

3. Create class "Cat" extending Animal:
   � Call parent constructor using super(name)
   � @Override makeSound() to print "Meow!"

4. Demonstrate polymorphism by storing Dog/Cat in Animal variables.

Inheritance Concepts:
� extends - inherits from parent class
� super() - calls parent constructor
� @Override - indicates method overriding
� protected - accessible in subclasses

Expected Output:
Buddy says: Woof! Whiskers says: Meow! -- Polymorphism Demo -- Woof! Meow!

Your Task: Use ArrayList to create a dynamic list of students, demonstrating add, remove, iterate, and search operations.

Detailed Requirements:
1. Import ArrayList: import java.util.ArrayList;

2. Create an ArrayList of Strings for student names:
   ArrayList<String> students = new ArrayList<>();

3. Add students using add() method - add at least 4 names.

4. Print all students using enhanced for loop:
   for (String student : students) { ... }

5. Remove a student using remove() method.

6. Check if student exists using contains() method.

7. Get ArrayList size using size() method.

ArrayList vs Array:
� ArrayList grows/shrinks dynamically (arrays are fixed size)
� ArrayList has built-in methods (add, remove, contains, etc.)
� ArrayList only holds objects (use Integer, not int)

Expected Output:
All students: - Alice - Bob - Charlie - Diana Total: 4 students After removing Bob: - Alice - Charlie - Diana Contains Alice? true Contains Bob? false