--- a/code/observer-example.java	Fri Aug 10 22:15:51 2007 +0200
+++ b/code/observer-example.java	Sat Aug 11 12:49:00 2007 +0200
@@ -1,31 +1,31 @@
-        import java.util.Observable;
-        import java.util.Observer;
+    import java.util.Observable;
+    import java.util.Observer;
 
-        public class MessageBoard extends Observable {
-          private String message;
+    public class MessageBoard extends Observable {
+      private String message;
 
-          public String getMessage() {
-            return message;
-          }
+      public String getMessage() {
+        return message;
+      }
 
-          public void changeMessage(String message) {
-            this.message = message;
-            setChanged();
-            notifyObservers(message);
-          }
+      public void changeMessage(String message) {
+        this.message = message;
+        setChanged();
+        notifyObservers(message);
+      }
 
-          public static void main(String[] args) {
-            MessageBoard board = new MessageBoard();
-            Student bob = new Student();
-            Student joe = new Student();
-            board.addObserver(bob);
-            board.addObserver(joe);
-            board.changeMessage("More Homework!");
-          }
-        }
+      public static void main(String[] args) {
+        MessageBoard board = new MessageBoard();
+        Student bob = new Student();
+        Student joe = new Student();
+        board.addObserver(bob);
+        board.addObserver(joe);
+        board.changeMessage("More Homework!");
+      }
+    }
 
-        class Student implements Observer {
-          public void update(Observable o, Object arg) {
-            System.out.println("Message board changed: " + arg);
-          }
-        }
+    class Student implements Observer {
+      public void update(Observable o, Object arg) {
+        System.out.println("Message board changed: " + arg);
+      }
+    }