#reading design pattern

package com.designpattern.behavioralpattern; /**  *  * @author collection  */ public class ChainfOfResponsibilityPattern {     public static void main(String[] args){         Logger logger, logger1, logger2;         logger = new StdoutLogger(Logger.DEBUG);         logger1 = logger.setNext(new EmailLogger(Logger.NOTICE));         logger2 = logger1.setNext(new StderrLogger(Logger.ERR));                 logger.message("Entering function y.", Logger.DEBUG);         logger.message("Step1 completed", Logger.NOTICE);         logger.message("An error has occurred.", Logger.ERR);             } } abstract class Logger{     public static int ERR = 3;     public static int NOTICE = 5;     public static int DEBUG = 7;     protected int mask;         protected Logger next;     public Logger setNext(Logger log){         next = log;         return log;     }     public void message(String msg, int priority){         if(priority <= mask){             writeMessage(msg);         }         if(next != null){             next.message(msg, priority);         }     }         abstract protected void writeMessage(String msg);    } class StdoutLogger extends Logger{         public StdoutLogger(int mask){         this.mask = mask;     }     @Override     protected void writeMessage(String msg) {         System.out.println("Writing to stdout: " + msg);     }     } class EmailLogger extends Logger{         public EmailLogger(int mask){         this.mask = mask;     }     @Override     protected void writeMessage(String msg) {         System.out.println("Sending via email: " + msg);     }     } class StderrLogger extends Logger{         public StderrLogger(int mask){         this.mask = mask;     }     @Override     protected void writeMessage(String msg) {         System.out.println("Sending to stderr: " + msg);     }     }

package com.designpattern.structuralpattern; import java.util.HashMap; import java.util.Map; /**  *  * @author shaiful islam(palash)  */ public class FlyweightPattern {     private static CoffeeFlavor[] flavors = new CoffeeFlavor[100];     private static CoffeeOrderContext[] tables = new CoffeeOrderContext[100];     private static int ordersMade = 0;     private static CoffeeFlavorFactory flavorFactory;         public static void takeOrders(String flavorIn, int table){         flavors[ordersMade] = flavorFactory.getCoffeeFlavor(flavorIn);         tables[ordersMade++] = new CoffeeOrderContext(table);     }         public static void main(String[] args){         flavorFactory = new CoffeeFlavorFactory();         takeOrders("Cappuccino", 2);         takeOrders("Xpresso", 121);         for (int i = 0; i < ordersMade; i++) {             flavors[i].serveCoffee(tables[i]);         }         System.out.println("total CoffeeFlavor objects made: " +  flavorFactory.getTotalCoffeeFlavorsMade());     }     } //Flyweight factory class CoffeeFlavorFactory{     private Map<String, CoffeeFlavor> flavors = new HashMap<String, CoffeeFlavor>();         public CoffeeFlavor getCoffeeFlavor(String flavorName){         CoffeeFlavor flavor = flavors.get(flavorName);         if(flavor == null){             flavor = new CoffeeFlavor(flavorName);             flavors.put(flavorName, flavor);         }         return flavor;     }         public int getTotalCoffeeFlavorsMade(){         return flavors.size();     } } interface CoffeOrder{     public void serveCoffee(CoffeeOrderContext context); } class CoffeeFlavor implements CoffeOrder{     private String flavor;         public CoffeeFlavor(String newFlavor){         this.flavor = newFlavor;     }         public String getFlavor(){         return this.flavor;     }         @Override     public void serveCoffee(CoffeeOrderContext context) {         System.out.println("Serving coffee flavor " +  flavor + " to table number " + context.getTable());     }     } class CoffeeOrderContext{     private int tableNumber;     public CoffeeOrderContext(int tableNumber){         this.tableNumber = tableNumber;     }     public int getTable(){         return this.tableNumber;     } }

/*  * To change this template, choose Tools | Templates  * and open the template in the editor.  */ package com.designpattern.structuralpattern; /**  *  * @author palash  */ public class BridgePattern {     public static void main(String[] args){         // first example         Fan fan = new Fan();         fan.switchOn();         Bulb bulb = new Bulb();         bulb.switchOff();                 // second example         Shape[] shapes = new Shape[]{             new CircleShape(1, 2, 3, new DrawingAPI1()),             new CircleShape(5, 7, 11, new DrawingAPI2()),         };         for(Shape shape : shapes){             shape.resizeByPercentage(2.5);             shape.draw();         }     } } // first example interface Switch{     public void switchOn();     public void switchOff(); } class Fan implements Switch{     @Override     public void switchOn() {         System.out.println("Fan's switch on");     }     @Override     public void switchOff() {         System.out.println("Fan's switch off");     }   } class Bulb implements Switch{     @Override     public void switchOn() {         System.out.println("Bulb's switch on");     }     @Override     public void switchOff() {         System.out.println("Bulb's switch off");     }     } /////////////////////////////////////// // second example //implementor interface DrawingAPI{     public void drawCircle(double x, double y, double radius); } // concreteImplementor class DrawingAPI1 implements DrawingAPI{     @Override     public void drawCircle(double x, double y, double radius) {         System.out.printf("API1.circle at %f:%f radius %f\n", x, y, radius);     } } // concreteImplementor class DrawingAPI2 implements DrawingAPI{     @Override     public void drawCircle(double x, double y, double radius) {         System.out.printf("API1.circle at %f:%f radius %f\n", x, y, radius);     }    } // abstraction abstract class Shape{     protected DrawingAPI drawingAPI;     protected Shape(DrawingAPI drawingAPI){         this.drawingAPI = drawingAPI;     }         public abstract void draw();     public abstract void resizeByPercentage(double pct); } class CircleShape extends Shape{     private double x,y,radius;         public CircleShape(double x, double y, double radius, DrawingAPI drawingAPI){         super(drawingAPI);         this.x = x;  this.y = y;  this.radius = radius;     }     @Override     public void draw() {         drawingAPI.drawCircle(x, y, radius);     }     @Override     public void resizeByPercentage(double pct) {         radius *= pct;     }     }

package com.designpattern.structuralpattern; /**  *  * @author palash  */ public class AdapterPattern {     public static void main(String[] args){               // class adapter pattern by inheritance         RectangularPlugClass clientPlug = new RectangularPlugClass("5amp", "15map");         System.out.println(clientPlug.getPower());                 // object adapter pattern by composition         RectangularPlugObject clientPlugObj = new RectangularPlugObject("7amp", "20amp");         System.out.println(clientPlugObj.getPower());     } } // class adapter pattern class CylindericalSocketClass{     public String supply(String cylinStem1, String cylinStem2){         System.out.println("Power...");         return cylinStem1 + " and " + cylinStem2 + " power supply from class adapter pattern";     } } class RectangularAdapterClass extends CylindericalSocketClass{     public String adapt(String rectaStem1, String rectaStem2){         String cylinStem1 = rectaStem1;         String cylinStem2 = rectaStem2;         return supply(cylinStem1, cylinStem2);     } } class RectangularPlugClass{     private String rectaStem1;     private String rectaStem2;     public RectangularPlugClass(String param1, String param2){         this.rectaStem1 = param1;         this.rectaStem2 = param2;     }         public String getPower(){         RectangularAdapterClass adapter = new RectangularAdapterClass();         String power = adapter.adapt(rectaStem1, rectaStem2);         return power;     } } /////////////////////////////////////////////// // Object adapter pattern class CylindericalSocketObject{     public String supply(String cylinStem1, String cylinStem2){         System.out.println("Power...");         return cylinStem1 + " and " + cylinStem2 + " power supply from object adapter pattern";     } } class RectangularAdapterObject{     private CylindericalSocketObject socket;         public String adapt(String rectaStem1, String rectaStem2){         socket = new CylindericalSocketObject();         String cylinStem1 = rectaStem1;         String cylinStem2 = rectaStem2;         return socket.supply(cylinStem1, cylinStem2);     } } class RectangularPlugObject{     private String rectaStem1;     private String rectaStem2;     public RectangularPlugObject(String param1, String param2){         this.rectaStem1 = param1;         this.rectaStem2 = param2;     }         public String getPower(){         RectangularAdapterObject adapter = new RectangularAdapterObject();         String power = adapter.adapt(rectaStem1, rectaStem2);         return power;     } }