[DesignPattern - Chain of Responsibility] sample1

Design Pattern - Chain of Responsibility

1. 클래스다이어그램

2. Source

• Trouble.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public class Trouble {
      private int number;
      public Trouble(int number) {
          this.number = number;
      }
      public int getNumber() {
          return number;
      }
      public String toString() {
          return "[Trouble" + number + "]";
      }
  }

• Support.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public abstract class Support {
      private String name;
      private Support next;
      public Support(String name) {
          this.name = name;
      }
      public Support setNext(Support next) {
          this.next = next;
          return next;
      }
      public final void support(Trouble trouble) {
          if(resolve(trouble)) {
              done(trouble);
          } else if(next != null) {
              next.support(trouble);
          } else {
              fail(trouble);
          }
      }
      public String toString() {
          return "[" + name + "]";
      }
      protected abstract boolean resolve(Trouble trouble);
      protected void done(Trouble trouble) {
          System.out.println(trouble + " is resolved by " + this + ".");
      }
      protected void fail(Trouble trouble) {
          System.out.println(trouble + " cannot be resolved.");
      }
  }

• NoSupport.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public class NoSupport extends Support {
      public NoSupport(String name) {
          super(name);
      }
      @Override
      protected boolean resolve(Trouble trouble) {
          return false;
      }
  }

• LimitSupport.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public class LimitSupport extends Support {
      private int limit;
      public LimitSupport(String name, int limit) {
          super(name);
          this.limit = limit;
      }
      @Override
      protected boolean resolve(Trouble trouble) {
          if(trouble.getNumber() < limit) {
              return true;
          } else {
              return false;
          }
      }
  }

• OddSupport.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public class OddSupport extends Support {
      public OddSupport(String name) {
          super(name);
      }
      @Override
      protected boolean resolve(Trouble trouble) {
          if(trouble.getNumber() % 2 == 1) {
              return true;
          } else {
              return false;
          }
      }
  }

• SpecialSupport.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public class SpecialSupport extends Support {
      private int number;
      public SpecialSupport(String name, int number) {
          super(name);
          this.number = number;
      }
      @Override
      protected boolean resolve(Trouble trouble) {
          if(trouble.getNumber() == number) {
              return true;
          } else {
              return false;
          }
      }
  }

• Main.java

  package com.dazzilove.chainofresponsibility.sample1;
  
  public class Main {
      public static void main(String[] args) {
          Support alice = new NoSupport("Alice");
          Support bob = new LimitSupport("Bob", 100);
          Support charlie = new SpecialSupport("Charlie", 429);
          Support diana = new LimitSupport("Diana", 200);
          Support elmo = new OddSupport("Elmo");
          Support fred = new LimitSupport("Fred", 300);
          //연쇄의 형성
          alice.setNext(bob).setNext(charlie).setNext(diana).setNext(elmo).setNext(fred);
          //다양한 트러블 발생
          for(int i=0; i<500; i += 33) {
              alice.support(new Trouble(i));
          }
      }
  }

3. 결과출력