Java Design Patterns Tutorial - Java Design Pattern - Mediator Pattern

Mediator pattern reduces communication between multiple objects.

This pattern provides a mediator class which handles all the communications between different classes.

Mediator pattern falls under behavioral pattern category.

Example

class Printer {/*  w  w  w.  j  a  v a 2 s .co m*/
   public static void showMessage(Machine user, String message){
      System.out.println(new java.util.Date().toString()
         + " [" + user.getName() +"] : " + message);
   }
}
class Machine {
   private String name;

   public Machine(String name){
      this.name  = name;
   }
   public String getName() {
      return name;
   }
   public void setName(String name) {
      this.name = name;
   }
   public void sendMessage(String message){
      Printer.showMessage(this,message);
   }
}
class Main {
   public static void main(String[] args) {
      Machine m1= new Machine("M1");
      Machine m2 = new Machine("M2");

      m1.sendMessage("Rebooting");
      m2.sendMessage("Computing");
   }
}