add Composite pattern

Author: JakubVojvoda

composite/Composite.py

@@ -0,0 +1,73 @@
+#
+# Python Design Patterns: Composite
+# Author: Jakub Vojvoda [github.com/JakubVojvoda]
+# 2016
+#
+# Source code is licensed under MIT License
+# (for more details see LICENSE)
+# 
+
+import sys
+
+#
+# Component
+# defines an interface for all objects in the composition
+# both the composite and the leaf nodes
+#
+class Component:
+  def getChild(self, index):
+    pass
+  
+  def add(self, component):
+    pass
+  
+  def remove(self, index):
+    pass
+  
+  def operation(self):
+    pass
+
+#
+# Composite
+# defines behavior of the components having children
+# and store child components
+#
+class Composite(Component):
+  def __init__(self):
+    Component.__init__(self)
+    self._children = []
+  
+  def getChild(self, index):
+    return self._children[index]
+  
+  def add(self, component):
+    self._children.append(component)   
+  
+  def remove(self, index):
+    self._children.remove(index)
+  
+  def operation(self):
+    for i in range(len(self._children)):
+      self._children[i].operation()
+      
+#
+# Leaf
+# defines the behavior for the elements in the composition,
+# it has no children
+#
+class Leaf(Component):
+  def __init__(self, index):
+    Component.__init__(self)
+    self._idx = index
+  
+  def operation(self):
+    print("Leaf " + str(self._idx) + " operation.")
+      
+
+if __name__ == "__main__":
+  composite = Composite()
+  
+  for i in range(5):
+    composite.add(Leaf(i))
+  
+  composite.operation()