//MoreVariables.java
//more demo of basic variables of int, String, and double type.
//demo of input and output with JOptionPane windows

import javax.swing.*;     //for JOptionPane

public class MoreVariables {
    public static void main (String [] args) {

	String name, input;   //String type for string of characters
	int age;              //int for integer value
	//double for real number value (can have .)
	double radius, circumference, area;
	//Use int for counting, double for measuring.

	name = "joe";     //assign to String object
	System.out.println( "Welcome: " + name );

	name = name + "smith";   //+ is string concatenation
	System.out.println( "and now it's: " + name );

	String firstName, lastName;
	firstName = "Fred";
	lastName = "Smith";
	
	name = firstName + " " + lastName;  
	System.out.println( "Welcome: " + name );

	//***********************************************
	//JOptionPane input and output dialog windows.
	//showInputDialog method has prompt string parameter,
	//  returns a String, assign it to a string variable:
	name = JOptionPane.showInputDialog( "Enter your name please" );

	//showMessageDialog displays a string
	JOptionPane.showMessageDialog( null, "Welcome: " + name );
	//null must be the first argument.
	//2nd argument is string, here concatenation.


	//***********************************************
	input = JOptionPane.showInputDialog( "Enter your age in years" );
	//to input an int, need to convert String to int:
	age = Integer.parseInt( input );   //extremely finicky
	age = age + 1;   
	JOptionPane.showMessageDialog( null, "Next birthday you will be: " + 
				              age );


	//***********************************************
	input = JOptionPane.showInputDialog( "Enter radius of a circle" );
	//to input a double, need to convert String to double:
	radius = Double.parseDouble( input );

	circumference = 2 * Math.PI * radius;
	area = Math.PI * radius*radius;

	JOptionPane.showMessageDialog( null, "Circumference=" + circumference +
				       "  Area=" + area);
    }
}