factory-method

I want to return an Interface and inside a switch statement I would like to set it. Is this a bad design? private IResultEntity GetEntity(char? someType) { IResultEntity entity = null; switch (someType) { case 'L': //life entity = new LifeEntity(); break; case 'P': //property entity = new PropertyEntity(); break; case 'D': //disability entity = new DisabilityEntity(); break; case 'C': //credit card entity = new CreditCardEntity(); break; } return entity; } Radu094 I don't usually mind switch statements in a factory, provided I can group and control all of the derived classes that I want my

I'm applying the Factory design pattern in my C++ project, and below you can see how I am doing it. I try to improve my code by following the "anti-if" campaign, thus want to remove the if statements that I am having. Any idea how can I do it? typedef std::map<std::string, Chip*> ChipList; Chip* ChipFactory::createChip(const std::string& type) { MCList::iterator existing = Chips.find(type); if (existing != Chips.end()) { return (existing->second); } if (type == "R500") { return Chips[type] = new ChipR500(); } if (type == "PIC32F42") { return Chips[type] = new ChipPIC32F42(); } if (type ==

Is it possible in Java to create a static factory method/class that uses an interface as the parameterized type and return an implementing class of this given interface? Although my knowledge of Generics is limited, here is what I want to do: // define a base interface: public interface Tool { // nothing here, just the interface. } // define a parser tool: public interface Parser extends Tool { public ParseObject parse(InputStream is); } // define a converter tool: public interface Converter extends Tool { public ConvertObject convert(InputStream is, OutputStream os); } // define a factory

This is a question regarding the best practice for creating an instance of a class or type from different forms of the same data using python. Is it better to use a class method or is it better to use a separate function altogether? Let's say I have a class used to describe the size of a document. (Note: This is simply an example. I want to know the best way to create an instance of the class not the best way to describe the size of a document.) class Size(object): """ Utility object used to describe the size of a document. """ BYTE = 8 KILO = 1024 def __init__(self, bits): self._bits = bits

What is the difference between the Builder design pattern and the Factory design pattern? Which one is more advantageous and why ? How do I represent my findings as a graph if I want to test and compare/contrast these patterns ? With design patterns, there usually is no "more advantageous" solution that works for all cases. It depends on what you need to implement. From Wikipedia: Builder focuses on constructing a complex object step by step. Abstract Factory emphasizes a family of product objects (either simple or complex). Builder returns the product as a final step, but as far as the

What is the basic difference between the Factory and Abstract Factory Patterns? With the Factory pattern, you produce instances of implementations ( Apple , Banana , Cherry , etc.) of a particular interface -- say, IFruit . With the Abstract Factory pattern, you provide a way for anyone to provide their own factory. This allows your warehouse to be either an IFruitFactory or an IJuiceFactory , without requiring your warehouse to know anything about fruits or juices. Sudhakar Kalmari Source for this information taken from: http://java.dzone.com/news/intro-design-patterns-abstract Abstract