solomon_13000 14 Junior Poster in Training

I found some reading materials about factory design pattern (parallel hierarchy) whereby a class in a hierarchy has a corresponding class in the another hierarchy. So I wrote the code as below:

package com.factory3;

public abstract class Subject {
     abstract SubjectPlanner createPlanner();
}

package com.factory3;

public class English extends Subject{
      public  SubjectPlanner createPlanner(){
          return new EnglishPlanner(this);
      }
}

package com.factory3;

public class Mathematic extends Subject{
      public SubjectPlanner createPlanner(){
          return new MathematicPlanner(this);
      }
}


package com.factory3;

import java.util.Date;

public abstract class SubjectPlanner {
     private Subject s;
     public SubjectPlanner(Subject s){
         this.s = s;
     }
     public abstract Date getAvailable();
}


package com.factory3;

import java.util.Date;

public class EnglishPlanner extends SubjectPlanner {
    public EnglishPlanner(Subject s) {
        super(s);
    }
    public Date getAvailable(){
        return new Date();
    }
}


package com.factory3;

import java.util.Date;

public class MathematicPlanner extends SubjectPlanner{
      public MathematicPlanner(Subject s){
          super(s);
      }
      public Date getAvailable(){
         return new Date();
      }
}


package com.factory3;

public class SubjectFactory {
     public static Subject getSubject(String s){
         if(s.equalsIgnoreCase("english")){
             return new English();
         }else{
             return new Mathematic();
         }
     }
}


package com.factory3;

public class Test {
    public static void main(String[] args){
        SubjectPlanner sp = SubjectFactory.getSubject("english").createPlanner();
        System.out.println(sp.getAvailable());
    }
}

Can I classify the code above as parallel hierarchy? Your help is kindly appreciated.

Thank You.

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