// Welcome1.java

// A first program in Java

public class Welcome1 {

public static void main( String args[] )

{

System.out.println( "Welcome to Java Programming!" );

}

}

// Welcome2.java

// Printing a line with multiple statements

public class Welcome2 {

public static void main( String args[] )

{

System.out.print( "Welcome to " );

System.out.println( "Java Programming!" );

}

}

// Welcome3.java

// Printing multiple lines with a single statement

public class Welcome3 {

public static void main( String args[] )

{

System.out.println( "Welcome\nto\nJava\nProgramming!" );

}

}

// Welcome4.java

// Printing multiple lines in a dialog box

import javax.swing.JOptionPane; // import class JOptionPane

public class Welcome4 {

public static void main( String args[] )

{

JOptionPane.showMessageDialog(

null, "Welcome\nto\nJava\nProgramming!" );

System.exit( 0 ); // terminate the program

}

}

// Addition.java

// An addition program

import javax.swing.JOptionPane; // import class JOptionPane

public class Addition {

public static void main( String args[] )

{

String firstNumber, // first string entered by user

secondNumber; // second string entered by user

int number1, // first number to add

number2, // second number to add

sum; // sum of number1 and number2

// read in first number from user as a string

firstNumber =

JOptionPane.showInputDialog( "Enter first integer" );

// read in second number from user as a string

secondNumber =

JOptionPane.showInputDialog( "Enter second integer" );

// convert numbers from type String to type int

number1 = Integer.parseInt( firstNumber );

number2 = Integer.parseInt( secondNumber );

// add the numbers

sum = number1 + number2;

// display the results

JOptionPane.showMessageDialog(

null, "The sum is " + sum, "Results",

JOptionPane.PLAIN_MESSAGE );

System.exit( 0 ); // terminate the program

}

}

// Comparison.java

// Using if statements, relational operators,

// and equality operators

import javax.swing.JOptionPane;

public class Comparison {

public static void main( String args[] )

{

String firstNumber, // first string entered by user

secondNumber, // second string entered by user

result; // a string containing the output

int number1, // first number to compare

number2; // second number to compare

// read first number from user as a string

firstNumber =

JOptionPane.showInputDialog( "Enter first integer:" );

// read second number from user as a string

secondNumber =

JOptionPane.showInputDialog( "Enter second integer:" );

// convert numbers from type String to type int

number1 = Integer.parseInt( firstNumber );

number2 = Integer.parseInt( secondNumber );

// initialize result to the empty string

result = "";

if ( number1 == number2 )

result = number1 + " == " + number2;

if ( number1 != number2 )

result = number1 + " != " + number2;

if ( number1 < number2 )

result = result + "\n" + number1 + " < " + number2;

if ( number1 > number2 )

result = result + "\n" + number1 + " > " + number2;

if ( number1 <= number2 )

result = result + "\n" + number1 + " <= " + number2;

if ( number1 >= number2 )

result = result + "\n" + number1 + " >= " + number2;

// Display results

JOptionPane.showMessageDialog(

null, result, "Comparison Results",

JOptionPane.INFORMATION_MESSAGE );

System.exit( 0 );

}

}