Factory Design Pattern

factory-design pattern.java

/*
Modelul de Design Factory este un model creational care ofera o interfata pentru crearea obiectelor intr-o superclasa, dar permite
subclaselor sa modifice tipul obiectelor care vor fi create. Acest model este deosebit de util cand avem nevoie de un mod de a crea
diferite obiecte, dar dorim sa separam codul clientului de clasele concrete
*/

abstract class Document {

         protected String name;
         protected String content;

         public void setName(String name) {
                this.name = name;
         }

         public void setContent(String content) {
                this.content = content;
         }

         public abstract void save();

}

class PDFDocument extends Document {

    @Override
    public void save() {

          System.out.println("Saving PDF document: " + name);
          System.out.println("Compressing and encrypting content");
    }

}

class WordDocument extends Document {


    @Override
    public void save() {

          System.out.println("Saving Word document: " + name);
          System.out.println("Formatting content");
    }

}

//Abstract Creator
abstract class DocumentFactory {

      //Factory method
      public abstract Document createDocument();

      //template method care foloseste metoda factory
      public Document prepareDocument(String name, String content) {

         Document document = createDocument();
         document.setName(name);
         document.setContent(content);
         return document;
      }
}

//concret Creators
class PDFDocumentFactory extends DocumentFactory {

      @Override
      public Document createDocument() {
             return new PDFDocument();
      }
}


class WordDocumentFactory extends DocumentFactory {

      @Override
      public Document createDocument() {
             return new WordDocument();
      }
}

//client code
public class DocumentManagementSystem {

       public static void main(String[] args) {

          //create a PDF document
          DocumentFactory pdfFactory = new PDFDocumentFactory();
          Document pdfdoc = pdfFactory.prepareDocument("Annual Raport","Financial data for 2025");
          pdfdoc.save();

          //create a Word document

          DocumentFactory wordFactory = new WordDocumentFactory();
          Document worddoc = wordFactory.prepareDocument("Meeting Minutes","Topics discussed in April meeting");
          pdfdoc.save();
       }
}