Removing Dependency from SDK Core Project

- Copied files required for Rest API SDK
- Removed PPApiContext and directly connected APIContext with PPConfigManager
- Removed duplicate data storage of configuration and credentials.
- Code Style Fixes
- Remove build.xml file as it is not required anymore
- Updated the samples
- Updated the documentations

lib/PayPal/Common/PPReflectionUtil.php

@@ -0,0 +1,102 @@
+<?php
+
+namespace PayPal\Common;
+
+/**
+ * Class PPReflectionUtil
+ *
+ * @package PayPal\Common
+ */
+class PPReflectionUtil
+{
+
+    /**
+     * Reflection Methods
+     *
+     * @var \ReflectionMethod[]
+     */
+    private static $propertiesRefl = array();
+
+    /**
+     * Properties Type
+     *
+     * @var string[]
+     */
+    private static $propertiesType = array();
+
+
+    /**
+     * Gets Property Class
+     *
+     * @param $class
+     * @param $propertyName
+     * @return string
+     */
+    public static function getPropertyClass($class, $propertyName)
+    {
+
+        if (($annotations = self::propertyAnnotations($class, $propertyName)) && isset($annotations['return'])) {
+            $param = $annotations['return'];
+        }
+
+        if (isset($param)) {
+            $anno = explode(' ', $param);
+            return $anno[0];
+        } else {
+            return 'string';
+        }
+    }
+
+    /**
+     * Retrieves Annotations of each property
+     *
+     * @param $class
+     * @param $propertyName
+     * @throws \RuntimeException
+     * @return mixed
+     */
+    public static function propertyAnnotations($class, $propertyName)
+    {
+        $class = is_object($class) ? get_class($class) : $class;
+        if (!class_exists('ReflectionProperty')) {
+            throw new \RuntimeException("Property type of " . $class . "::{$propertyName} cannot be resolved");
+        }
+
+        if ($annotations =& self::$propertiesType[$class][$propertyName]) {
+            return $annotations;
+        }
+
+        if (!($refl =& self::$propertiesRefl[$class][$propertyName])) {
+            $getter = method_exists($class, "get" . ucfirst($propertyName)) ?
+                "get" . ucfirst($propertyName) :
+                "get" . preg_replace_callback("/([_\-\s]?([a-z0-9]+))/", "self::replace_callback", $propertyName);
+            $refl = new \ReflectionMethod($class, $getter);
+            self::$propertiesRefl[$class][$propertyName] = $refl;
+        }
+
+        // todo: smarter regexp
+        if ( !preg_match_all(
+            '~\@([^\s@\(]+)[\t ]*(?:\(?([^\n@]+)\)?)?~i',
+            $refl->getDocComment(),
+            $annots,
+            PREG_PATTERN_ORDER)) {
+            return null;
+        }
+        foreach ($annots[1] as $i => $annot) {
+            $annotations[strtolower($annot)] = empty($annots[2][$i]) ? TRUE : rtrim($annots[2][$i], " \t\n\r)");
+        }
+
+        return $annotations;
+    }
+
+    /**
+     * preg_replace_callback callback function
+     *
+     * @param $match
+     * @return string
+     */
+    private static function replace_callback($match)
+    {
+        return ucwords($match[2]);
+    }
+}