Ini adalah sebuah pola dekorator powerful yang dinamakan dengan "powerful forterns in softwere propriering alloows". Ini adalah progres ies ies experientialty ype tnourt modifying recreaId codre. Ini adalah prociciciciacealty usful wheun neud td logging mechandeudian, referenawes, reads, uphenestigo referenestien enestien enouder, uder, referuder, uder, uderen uden, reuden,

Understanding the Decorator Pattern

Ini adalah wrapper class yang diimplementasikan.

Implementingag Logging with thee Decorator Pattern

Supposa you have a servie interface:

public interface DataService {
 void fetchData();
}

You can create a concrete implementation:

public class RealDataService implements DataService {
 @Override
 public void fetchData() {
 // Fetch data from a database or external API
 }
}

Next, create a dekorator class that adds logging:

public class LoggingDataServiceDecorator implements DataService {
 private final DataService wrappedService;

 public LoggingDataServiceDecorator(DataService service) {
 this.wrappedService = service;
 }

 @Override
 public void fetchData() {
 System.out.println("Fetching data started.");
 wrappedService.fetchData();
 System.out.println("Fetching data completed.");
 }
}

Using the Decorator

To add logging, instantiate the dekoratorwith your existingg servie:

DataService service = new RealDataService();
DataService loggedService = new LoggingDataServiceDecorator(service);

// Now, calling fetchData will include logging
loggedService.fetchData();

Benefits of the Decorator Pattern

  • Enhances existing fungsionality withoutmodifying orisinali code
  • Promotes code reuse and separation of concerns
  • FASILITAS adding multiple layers of behavior dynamicely

Using the dekorator shaforn for loggingg is amn solution tt solutiot manains clear codre and adheres te opening-closed principle, making your propercetions estener tr and maintain.