OOPS concepts:
Object-Oriented Programming (OOP) is centered on creating classes and objects
in Java.
Type of oops concept in java:
- classes and object
- Inheritance
- Polymorphism
- Abstraction
- Encapsulation
Classes and Object
A blueprint for making objects is a class. It specifies the attributes and
actions that should be present in objects belonging to that class. An instance
of a class is an object.
Example:
public class Person {
// create class
private String name;
private int age;
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public int getAge() {
return age;
}
public void sayHello() {
System.out.println("Hello, my name is " + name +
" and I am " + age + " years old.");
}
}
public class Main {
public static void main(String[] args) {
Person person1 = new Person("John", 30);
// create object
Person person2 = new Person("Jane", 25);
System.out.println(person1.getName() + " is " +
person1.getAge() + " years old.");
System.out.println(person2.getName() + " is " +
person2.getAge() + " years old.");
person1.sayHello();
person2.sayHello();
// calling
}
}
Output:
John is 30 years old.
Jane is 25 years old.
Hello, my name is John and I am 30 years old.
Hello, my name is Jane and I am 25 years old.
