App.java

class ApiException extends Exception {}


@FunctionalInterface
interface ServiceBlock<T> {
  T call() throws ApiException;
}

@FunctionalInterface
interface ExceptionBlock<T> {
  T fallback();
}

public class ExceptionHandler {
  public static <T> T run(ServiceBlock<T> call, ExceptionBlock<T> exceptionBlock) {
    try {
      return call.call();
    } catch (ApiException e) {
      return exceptionBlock.fallback();
    }
  }
}

class AdGroup {  }
class Feed {  }

class AddService {

  void callFunctions() {

    ExceptionBlock<AdGroup> genericFallback = () -> {
      System.out.println("do something generic");
      return null;
    };

    ExceptionHandler.run(() -> null, genericFallback);
    ExceptionHandler.run(() -> {
      System.out.println("another block");
      return null;
    }, genericFallback);
    ExceptionHandler.run((ServiceBlock<Boolean>) () -> null, () -> null);
    ExceptionHandler.run((ServiceBlock<Feed>) () -> null, () -> null);
    ExceptionHandler.run((ServiceBlock<String>) () -> null, () -> null);
    ExceptionHandler.run(() -> null, () -> null);
    
  }
}