import java.util.Scanner;

public class InputExample {
    public static void main(String[] args) {
        // Create a Scanner object to read input
        Scanner scanner = new Scanner(System.in);

        // String
        System.out.print("Enter your name: ");
        String name = scanner.nextLine();
    
        // Number
        System.out.print("Enter your number: ");
        Int number = scanner.nextInt();

        // Display a greeting with the user's name
        System.out.println("Hello, " + name + "!");

        // Close the Scanner object to release resources
        scanner.close();
    }
}
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public class InputExample {
    public static void main(String[] args) {

    }
}
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The keyword public indicates that this class is accessible from other classes
The class name (InputExample in this case) should match the file name (e.g., InputExample.java)

public static void main(String[] args) {:
Let's break down the parts of this method signature:

• public: This keyword specifies that the main method can be called from outside of the class.
• static: This keyword indicates that the main method belongs to the class itself rather than to instances of the class. This allows the Java runtime to call the main method without creating an object of the class.
• void: This specifies that the main method does not return any value.
• main: This is the name of the method. It must be written exactly as main.
• (String[] args): This is the parameter list for the main method. It accepts an array of strings as arguments. These arguments can be passed to the program when it is executed from the command line. For example, if you run java InputExample arg1 arg2, then args will contain ["arg1", "arg2"].

An instance is an object created from a class blueprint.

How to create instances?

• Use constructor, creates and initializes instances

A constructor always returns an instance of the class it's in (that is, a constructor in the Triangle class returns a triangle).

How to use constructor?
We call it like any other function
The only difference is that because we are creating a new Triangle instance,
we have to use the new keyword

ClassName instanceName = new ConstructorName();
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public class Triangle {
    double base;
    double height;

    // Constructor Declaration
    public Triangle(double base, double height) {
        this.base = base;
        this.height = height;
    }

    // Method below
    public double findArea() {
        this.base = this.height / 2;
    }
}
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What is true about a constructor function?
It always returns an instance of the class that it is in.

• • A constructor is used to create instances of the class that it is located in.

When is an attribute accessible in a class?

• It is always accessible inside a class.
  An attribute variable is accessible to every function and constructor inside the class.

If numOfSides is a static class integer variable of the Triangle class, then how would you correctly access this variable inside the main function?

• System.out.println(mytriangle.numOfSides);
  Incorrect
  An object instance is not needed for a static class variable.

• System.out.println(Triangle.numOfSides);

• For static variables, you can type the class name followed by a period (dot) to access it.

Generics are a way to tell a compiler what type of object a collection can contain.