creational/builder: implement the abstract factory

README.md

@@ -15,7 +15,7 @@ A curated collection of idiomatic design & application patterns for Go language.
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Abstract Factory](/creational/abstract_factory.md) | Provides an interface for creating families of releated objects | ✘ |
+| [Abstract Factory](/creational/abstract_factory.md) | Provides an interface for creating families of releated objects | ✔ |
 | [Builder](/creational/builder.md) | Builds a complex object using simple objects | ✔ |
 | [Factory Method](/creational/factory.md) | Defers instantiation of an object to a specialized function for creating instances | ✔ |
 | [Object Pool](/creational/object-pool.md) | Instantiates and maintains a group of objects instances of the same type | ✔ |

creational/abstract-factory.md

@@ -0,0 +1,55 @@
+# Abstract Factory Method Pattern
+
+Abstract Factory method creational design pattern allows providing interface that creating objects without having to specify the exact type of the object that will be created.
+
+## Implementation
+
+The example implementation shows how to make a phone from different copmanies.
+
+### Types
+
+```go
+package company
+
+type iCompnayFactory interface {
+	makePhone() iPhone
+}
+```
+
+### Different Implementations
+
+```go
+package company
+
+type CompnayType int
+
+const (
+	SAMSNUG CompnayType = iota
+	APPLE
+)
+
+func getCompnayFactory(compnay CompnayType) (iCompnayFactory, error) {
+	switch compnay {
+	case SAMSNUG:
+		return &samsungFactory{}, nil
+	case APPLE:
+		return &appleFactory{}, nil
+	default:
+		return nil, fmt.Errorf(/* .. */)
+	}
+}
+```
+
+## Usage
+
+With the abstract factory method, the user can provide an interface for creating families of releated objects.
+
+```go
+appleFactory, _ := getCompnayFactory(APPLE)
+applePhone := appleFactory.makePhone();
+applePhone.makeCall(/*...*/);
+
+samsungFactory, _ := getCompnayFactory(SAMSNUG)
+samsungPhone := samsungFactory.makePhone();
+samsungPhone.makeCall(/*...*/);
+```