Hello JavaWorld

The programm Hello World is the default application to show us how we use the simple parts from a (new) programming language. And so we take more than one look at Java.

The default sample

package biz.ritter.java; 
/**
 * Title:        Make Java - How To 
 * Description:  A simple 'Hello World' - Application 
 * Copyright:    Copyright © 2009 
 * Licence:      BSD 
 * @author Sebastian Ritter 
 * @version 1.0.0.0 
 */ 

public class HelloWorldSimple {          
  /** The first method for Java application is:  
   *  public static void main (String [] arg) {} 
   *  final call we do not change the arg variable. 
   *  This discription is a Java comment for tool javadoc.
   *  @param String [] parameter - here ignored 
   */   
  public static void main (final String [] ignored) { 
    /* Die follow line display the sentence. 
       This is a multi line comment. Tool javadoc ignore these.
     */ 
    System.out.println ("Hello World say's Bastie!"); // An end of line comment 
  } 
} 

Object-oriented

package biz.ritter.java;
/**
 * Title:        Make Java - How To
 * Description:  An object-oriented 'Hello World' - application
 * Copyright:    Copyright © 2009
 * Licence:      BSD
 * @author Sebastian Ritter
 * @version 1.0.0.0
 */
public class HelloWorldOO {
  /** The first method for Java application is:  
   *  public static void main (String [] arg) {} 
   *  final call we do not change the arg variable. 
   *  This discription is a Java comment for tool javadoc.
   *  
   *  With keyword static the method is defined as class method.
   *  Class methods can be called without creating object instance.
   *  @param String [] parameter - here ignored 
   */
  public static void main(final String [] ignored) {


/* Create an object and set variable helloWorldOO with reference to these instance */
 final HelloWorldOO helloWorldOO = new HelloWorldOO ();

 /* Call the method at our object and give needed parameters. */
 helloWorldOO.say ("Hello World.\nJava is object-oriented!\n");
 }

 /** Our self defined method 'say' display the text on console.
 *  @param String parameter with text to display
 */
 public void say (final String text){
 /* Display given text */
 System.out.println (text);
 }
}

The other way

package biz.ritter.java;
/**
 * Title:        Make Java - How To
 * Description:  An other way for 'Hello World' - application
 * Copyright:    Copyright © 2009
 * License:      BSD
 * @author Sebastian Ritter
 * @version 1.0.0.0
 */ 
public class HelloWorldStatic { 
  /** This static block is calling, when our class HelloWorldStatic
   *  is loading from Java Virtual Machine [JVM].
   */
  static {
    System.out.print ("Hello World - an other version");
  } 

  /** The first method for Java application is:  
   *  public static void main (String [] arg) {} 
   *  final call we do not change the arg variable. 
   *  This discription is a Java comment for tool javadoc.
   *  @param String [] parameter - here ignored 
   */
  public static void main(final String [] ignored) {
    /* We leave our application and th JVM with this method.*/
    System.exit (0);
  }
}