Added decorator

README.md

@@ -19,7 +19,7 @@ Tested on: GNU Fortran (GCC) 4.8.
 - [X] Bridge
 - [X] Composite
 - [X] Criteria
-- [ ] Decorator
+- [X] Decorator
 - [ ] Façade
 - [ ] Flyweight
 - [ ] Proxy

structural/decorator/decorator_main.f90

@@ -0,0 +1,35 @@
+!Copyright (c) 2013 Farhan J. Khan
+!THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+!IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+!FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+!COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+!IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+!CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+!Main Program
+program decorator_main
+	use decorator_module
+	implicit none
+
+ 	class(shape), allocatable :: circle_shape
+	class(shape), allocatable :: rectangle_shape
+ 	class(shape), allocatable :: redCircle_shape
+ 	class(shape), allocatable :: redRectangle_shape
+	type(circle) :: theCircle
+
+ 	allocate(circle_shape, source=theCircle)
+ 	print *, 'Circle with normal border:'
+ 	call circle_shape%draw
+ 	allocate(redCircle_shape, source=redShapeDecorator(circle_shape))
+	print *, 'Circle with red border:'
+	call redCircle_shape%draw
+	allocate(rectangle_shape, source=rectangle())
+	allocate(redRectangle_shape, source = redShapeDecorator(rectangle_shape))
+	print *, 'Rectangle with red border:'
+	call redRectangle_shape%draw
+
+ 	deallocate(circle_shape)
+ 	deallocate(redCircle_shape)
+ 	deallocate(redRectangle_shape)
+
+end program decorator_main

structural/decorator/decorator_module.f90

@@ -0,0 +1,61 @@
+!Copyright (c) 2013 Farhan J. Khan
+!THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+!IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+!FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+!COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+!IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+!CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+!Module for defining decorator
+module decorator_module
+	implicit none
+
+	type, abstract :: shape
+	contains
+		procedure(drawInterface), deferred :: draw
+	end type shape
+	abstract interface
+		subroutine drawInterface(this)
+			import shape
+			class(shape), intent(in) :: this
+		end subroutine 
+	end interface
+
+	type, extends(shape) :: rectangle
+	contains
+		procedure :: draw => drawRectangle
+	end type rectangle
+
+	type, extends(shape) :: circle
+	contains
+		procedure :: draw => drawCircle
+	end type circle
+
+	type, extends(shape), abstract :: shapeDecorator
+	end type shapeDecorator
+
+	type, extends(shapeDecorator) :: redShapeDecorator
+		class(shape), pointer :: decoratedShape
+	contains
+		procedure :: draw => drawWithRedShapeDecorator
+	end type redShapeDecorator
+
+contains
+
+	subroutine drawRectangle(this)
+		class(rectangle), intent(in) :: this
+		print *, "Draw rectangle"
+	end subroutine 
+
+	subroutine drawCircle(this)
+		class(circle), intent(in) :: this
+		print *, "Draw circle"
+	end subroutine 
+
+	subroutine drawWithRedShapeDecorator(this)
+		class(redShapeDecorator), intent(in) :: this
+		call this%decoratedShape%draw
+		print *, "Red Border"
+	end subroutine 
+
+end module decorator_module