The observer pattern for Java design Patterns

http://www.verejava.com/?id=16999149610674

Package Com.observer.theory;public class test{public static void Main (string[] args) {StockData data=new St                Ockdata (16.1f,15.0f,17.2f,16.9f);        Buyer buyer=new Buyer (data);                Trading trading=new Trading (data);        Data.setstockdata (16.1f,15.0f,17.4f,16.9f);            Data.setstockdata (16.1f,14.5f,17.4f,16.9f); }}package com.observer.theory;import Java.util.observable;import Java.util.observer;public class Trading implements    observer{public Trading (Observable o) {o.addobserver (this);            } @Override public void update (Observable o, Object Arg) {if (o instanceof stockdata) {            StockData data= (stockdata) o;            SYSTEM.OUT.PRINTLN ("Transaction report:");            System.out.print ("Open Price:" +data.getopen ());            System.out.print ("Closing price:" +data.getclose ());            System.out.print ("Lowest Price:" +data.getlow ());            System.out.print ("High Price:" +data.gethigh ());        System.out.println (""); }   }}package com.observer.theory;import Java.util.observable;import java.util.observer;public class Buyer Implemen    TS observer{public Buyer (Observable o) {o.addobserver (this);            } @Override public void update (Observable o, Object Arg) {if (o instanceof stockdata) {            StockData data= (stockdata) o;            SYSTEM.OUT.PRINTLN ("Buyer Report:");            System.out.print ("Open Price:" +data.getopen ());            System.out.print ("Closing price:" +data.getclose ());            System.out.print ("Lowest Price:" +data.getlow ());            System.out.print ("High Price:" +data.gethigh ());        System.out.println (""); }}}package com.observer.theory;import java.util.observable;import Java.util.observer;public class StockData ex    Tends observable{private float open;    private float low;    private float high;    private float close;        Public StockData (float open, float low, float high, float close) {super ();        This.open = open; THis.low = low;        This.high = high;    This.close = close;    } public float Getopen () {return open;    } public void Setopen (float open) {this.open = open;    } public float Getlow () {return low;    } public void Setlow (float low) {this.low = low;    } public float Gethigh () {return high;    } public void Sethigh (float high) {This.high = high;    } public float Getclose () {return close;    } public void Setclose (float close) {this.close = close;        } public void Setstockdata (float open, float low, float high, float close) {this.open = open;        This.low = low;        This.high = high;            This.close = close;        Setchanged ();    Notifyobservers (); }    }

http://www.verejava.com/?id=16999149610674

The observer pattern for Java design Patterns