README NullObject

NullObject/NullLogger.php

@@ -3,23 +3,6 @@
 namespace DesignPatterns\NullObject;
 
 /**
- * NullOutput is a example of NullObject pattern. It is not formely a Design
- * Pattern by the GoF but it's a schema which appears frequently enough to
- * be a pattern. Futhermore it is a really good pattern in my opinion :
- * - the code in the client is simple
- * - it reduces the chance of null pointer exception
- * - less "if" => less test cases
- * 
- * The purpose : every time you have a method which returns an object or null,
- * you should return an object or a "NullObject". With NullObject, you don't need
- * statement like "if (!is_null($obj)) { $obj->callSomething(); }" anymore.
- *  
- * In this case, this a logger which does nothing. Other examples :
- * - null logger of symfony profiler
- * - null output in symfony/console 
- * - null handler in a Chain of Responsiblities pattern
- * - null command in a Command pattern
- * 
  * Performance concerns : ok there is a call for nothing but we spare an "if is_null"
  * I didn't run a benchmark but I think it's equivalent.
  * 
@@ -29,7 +12,7 @@ namespace DesignPatterns\NullObject;
 class NullLogger implements LoggerInterface
 {
     /**
-     * @param string $str
+     * {@inheritdoc}
      */
     public function log($str)
     {

NullObject/README.md

@@ -0,0 +1,20 @@
+# Null Object
+
+## Purpose
+
+NullOutput is a example of NullObject pattern. It is not formally a Design Pattern by the GoF but it's a schema which appears frequently enough to
+be a pattern. Furthermore it is a really good pattern in my opinion:
+
+* the code in the client is simple
+* it reduces the chance of null pointer exception
+* less "if" => less test cases
+
+Every time you have a method which returns an object or null, you should return an object or a `NullObject`. With NullObject, you don't need
+a statement like `if (!is_null($obj)) { $obj->callSomething(); }` anymore.
+
+## Examples
+
+* Symfony2: null logger of profiler
+* Symfony2: null output in Symfony/Console
+* null handler in a Chain of Responsibilities pattern
+* null command in a Command pattern