Add Composite Design Pattern and README.md in some folders

Author: Hyunk3l

.gitignore

@@ -1,2 +1,3 @@
 /vendor/
-.idea/
+/.idea/
+/coverage/

Behavioral/README.md

@@ -7,4 +7,4 @@
 Running Unit Tests
 
 * Run `composer install`
-* Now launch UTs running `vendor/bin/phpunit Creational/`
+* Now launch UTs running `vendor/bin/phpunit Tests/`

Creational/README.md

@@ -0,0 +1,62 @@
+<?php
+
+namespace PhpDesignPatterns\Structural\Composite;
+
+/**
+ * Class Phone (Composite object).
+ * @package PhpDesignPatterns\Structural\Composite
+ */
+class Phone extends PhoneElement
+{
+    /**
+     * List of PhoneElement.
+     *
+     * @var array of PhoneElement
+     */
+    private $elements;
+
+    /**
+     * Build a phone.
+     *
+     * @return string
+     */
+    public function build()
+    {
+        $phone = "";
+        if(empty($this->elements)) {
+            return $phone;
+        }
+
+        foreach($this->elements as $element)
+        {
+            $phone .= $element->build();
+        }
+        return $phone;
+    }
+
+    /**
+     * Add a PhoneElement child.
+     *
+     * @param PhoneElement $element
+     * @return PhoneDisplay
+     */
+    public function add(PhoneElement $element)
+    {
+        $this->elements[] = $element;
+        return $this;
+    }
+
+    /**
+     * Removes a child.
+     *
+     * @param mixed $child_key
+     * @return PhoneDisplay
+     */
+    public function remove($child_key)
+    {
+        if(!empty($this->elements[$child_key])) {
+            unset($this->elements[$child_key]);
+        }
+        return $this;
+    }
+}

README.md

@@ -0,0 +1,42 @@
+<?php
+
+namespace PhpDesignPatterns\Structural\Composite;
+
+/**
+ * Class PhoneButton
+ * @package PhpDesignPatterns\Structural\Composite
+ */
+class PhoneButton extends PhoneElement
+{
+    /**
+     * Build a phone button.
+     *
+     * @return string
+     */
+    public function build()
+    {
+        return "This is a phone button.".PHP_EOL;
+    }
+
+    /**
+     * Add a PhoneElement child.
+     *
+     * @param PhoneElement $element
+     * @return PhoneButton
+     */
+    public function add(PhoneElement $element)
+    {
+        return $this;
+    }
+
+    /**
+     * Removes a child.
+     *
+     * @param mixed $child_key
+     * @return PhoneButton
+     */
+    public function remove($child_key)
+    {
+        return $this;
+    }
+}

Structural/Composite/Phone.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace PhpDesignPatterns\Structural\Composite;
+
+/**
+ * Class PhoneDisplay
+ * @package PhpDesignPatterns\Structural\Composite
+ */
+class PhoneDisplay extends PhoneElement
+{
+    /**
+     * Build a phone display.
+     *
+     * @return string
+     */
+    public function build()
+    {
+        return "This is a phone display.".PHP_EOL;
+    }
+
+    /**
+     * Add a PhoneElement child.
+     *
+     * @param PhoneElement $element
+     * @return PhoneDisplay
+     */
+    public function add(PhoneElement $element)
+    {
+        return $this;
+    }
+
+    /**
+     * Removes a child.
+     *
+     * @param mixed $child_key
+     * @return PhoneDisplay
+     */
+    public function remove($child_key)
+    {
+        return $this;
+    }
+}

Structural/Composite/PhoneButton.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace PhpDesignPatterns\Structural\Composite;
+
+/**
+ * Class PhoneElement
+ * @package PhpDesignPatterns\Structural\Composite
+ */
+abstract class PhoneElement
+{
+    /**
+     * Builds an element.
+     * @return string
+     */
+    abstract public function build();
+
+    /**
+     * @param PhoneElement $element Element to add.
+     * @return PhoneElement
+     */
+    abstract public function add(PhoneElement $element);
+
+    /**
+     * Remove a PhoneElement child.
+     *
+     * @param mixed $child_key
+     * @return PhoneElement
+     */
+    abstract public function remove($child_key);
+}

Structural/Composite/PhoneDisplay.php

@@ -0,0 +1,8 @@
+# Composite Design Pattern
+
+### Intent
+
+“Compose objects into tree structures to represent part-whole hierarchies. Composite lets clients treat individual objects and compositions of objects uniformly.”
+
+Excerpt From: Erich Gamma. “Design Patterns: Elements of Reusable Object-Oriented Software.” 
+