Polymorphism, Generics and Encapsulation Polymorphism Polymorphism is the ability of an object to take on a variety of different forms or behaviors, depending on the context or situation in which the object is used. The data types that can be used to perform polymorphism are “superclass” and polymorphism can be performed on classes with "implements" or classes with "extends". Example: //polymorphism void main() { Hero h1 = Hero01(); h1.armor(); h1.hp(); } //abstract class abstract class Hero { armor() { print('000'); } hp() { print('000'); } } class Hero01 extends Hero { @override hp() { print('800'); } } image 1 output form polymorphism Generics Generics allow the creation of classes, functions, or data structures that can be generalized to work with different data types, thus increasing flexibility and type safety at compile time. Example : // Example of generic class class Box { T value; Box(this.value); T takeValue() { return value; } } void main() { // Create a Box object with type int var boxInt = Box(10); print(boxInt.takeValue()); // Output: 10 // Create a Box object with type String var boxString = Box('Dart'); print(boxString.takeValue()); // Output: Dart } image 2 output from generics Encapsulation Separates the internal parts of an object from the parts that can be accessed from outside the object. Helps protect data from unauthorized access or modification. Reduce potential bugs in the program. And allows changes to one part of the code without affecting other parts of the code. Setter and Getter Setter: - Setters are methods used to set or assign the value of an attribute or property. - Setters are generally used to provide write-only access or to provide validation before a value is set. - Setter names usually begin with the word "set" and are followed by the name of the attribute or property to be set. Getter: - Getter is a method used to get the value or read the value of an attribute or property. - Getters are generally used to provide read-only access to attributes or properties. - Getter names usually begin with the word "get" and are followed by the name of the attribute or property to be read. Example: class Car { // Private attributes String _color; int _yearOfProduction; // Constructor Car(this._color, this._yearOfProduction); // Getter and Setter for color String get color => _color; set color(String value) => _color = value; // Getter and Setter for year of production int get yearOfProduction => _yearOfProduction; set yearOfProduction(int value) => _yearOfProduction = value; // Public methods void infoCar() { print('Color: $_color, Year of Production: $yearOfProduction'); } } void main() { // Create a Car object var car = Car('Red', 2022); // Call the infoCar method car.infoCar(); // Output: Color: Red, Year of Production: 2022 } image 3 example of ecapsulation