diff --git a/composer.json b/composer.json
old mode 100644
new mode 100755
index 7db719e..44d5b91
--- a/composer.json
+++ b/composer.json
@@ -8,5 +8,10 @@
             "email": "ahwelp@universo.univates.br"
         }
     ],
+    "autoload" : {
+        "psr-4" : {
+            "RequestResponse\\" : "src/RequestResponse/"
+        }
+    },
     "require": {}
 }
diff --git a/src/RequestResponse/Flash.php b/src/RequestResponse/Flash.php
index b0df6a2..774380f 100755
--- a/src/RequestResponse/Flash.php
+++ b/src/RequestResponse/Flash.php
@@ -32,23 +32,26 @@ class Flash{
         if(session_id() == '' || !isset($_SESSION)) {
             session_start();
         }
-        $this->old_messages = $_SESSION['flashes'];
+        if( isset($_SESSION['flashes']) ){
+            $this->old_messages = $_SESSION['flashes'];
+        }
         unset( $_SESSION[self::SESSION_NAME] );
     }
 
     private static function newObj(){
-        if (!isset( self::$_response )) {
-            self::$_response = new Flash();
+        if (!isset( self::$_instance )) {
+            self::$_instance = new Flash();
         }
-        return self::$_response;
+        return self::$_instance;
     }
 
-    public function getInstance(){
-        if (!isset(self::$_response)) {
+    public static function getInstance(){
+        if (!isset(self::$_instance)) {
             return self::newObj();
         }
-        return self::$_response;
+        return self::$_instance;
     }
+
     //=======================================================
 
     public function load_to_session(){
diff --git a/src/RequestResponse/Request.php b/src/RequestResponse/Request.php
index 5f7b7ba..53afc35 100755
--- a/src/RequestResponse/Request.php
+++ b/src/RequestResponse/Request.php
@@ -1,11 +1,44 @@
 <?php
 namespace RequestResponse;
 
-use RequestResponse\Response as Response;
-
 class Request{
 
-    function required_param($parname, $type) {
+    const PARAM_ALPHA = 'alpha';
+    const PARAM_ALPHANUM = 'alphanum';
+    const PARAM_ALPHAEXT = 'alphaext';
+    const PARAM_ALPHANUMEXT = 'alphanumext';
+    const PARAM_INT = 'int';
+    const PARAM_FLOAT = 'float';
+    const PARAM_BOOL = 'bool';
+    const PARAM_RAW = 'raw';
+    const PARAM_TEXT = 'text';
+
+    const PARAM_AUTH = 'auth';
+    const PARAM_BASE64 = 'base64';
+    const PARAM_CAPABILITY = 'capability';
+    const PARAM_CLEANHTML = 'cleanhtml';
+    const PARAM_EMAIL = 'email';
+    const PARAM_FILE = 'file';
+    const PARAM_HOST = 'host';
+    const PARAM_LANG = 'lang';
+    const PARAM_LOCALURL = 'localurl';
+    const PARAM_NOTAGS = 'notags';
+    const PARAM_PATH = 'path';
+    const PARAM_PEM = 'pem';
+    const PARAM_PERMISSION = 'permission';
+    const PARAM_RAW_TRIMMED = 'raw_trimmed';
+    const PARAM_SAFEDIR = 'safedir';
+    const PARAM_SAFEPATH = 'safepath';
+    const PARAM_SEQUENCE = 'sequence';
+    const PARAM_TAG = 'tag';
+    const PARAM_TAGLIST = 'taglist';
+    const PARAM_THEME = 'theme';
+    const PARAM_URL = 'url';
+    const PARAM_USERNAME = 'username';
+    const PARAM_STRINGID = 'stringid';
+
+
+    public static function required_param($parname, $type) {
         if (func_num_args() != 2 or empty($parname) or empty($type)) {
             throw new \Exception('required_param() requires $parname and $type to be specified (parameter: '.$parname.')');
         }
@@ -25,7 +58,7 @@ class Request{
         return self::clean_param($param, $type);
     }
 
-    function required_param_array($parname, $type) {
+    public static function required_param_array($parname, $type) {
         if (func_num_args() != 2 or empty($parname) or empty($type)) {
             throw new \Exception('required_param_array() requires $parname and $type to be specified (parameter: '.$parname.')');
         }
@@ -99,20 +132,6 @@ class Request{
         return $result;
     }
 
-    /**
-     * Used by {@link optional_param()} and {@link required_param()} to
-     * clean the variables and/or cast to specific types, based on
-     * an options field.
-     * <code>
-     * $course->format = clean_param($course->format, PARAM_ALPHA);
-     * $selectedgradeitem = clean_param($selectedgradeitem, PARAM_INT);
-     * </code>
-     *
-     * @param mixed $param the variable we are cleaning
-     * @param string $type expected format of param after cleaning.
-     * @return mixed
-     * @throws coding_exception
-     */
     public static function clean_param($param, $type) {
         global $CFG;
 
@@ -127,45 +146,45 @@ class Request{
         }
 
         switch ($type) {
-            case PARAM_RAW:
+            case self::PARAM_RAW:
                 // No cleaning at all.
                 $param = fix_utf8($param);
                 return $param;
 
-            case PARAM_RAW_TRIMMED:
+            case self::PARAM_RAW_TRIMMED:
                 // No cleaning, but strip leading and trailing whitespace.
                 $param = fix_utf8($param);
                 return trim($param);
 
-            case PARAM_INT:
+            case self::PARAM_INT:
                 // Convert to integer.
                 return (int)$param;
 
-            case PARAM_FLOAT:
+            case self::PARAM_FLOAT:
                 // Convert to float.
                 return (float)$param;
 
-            case PARAM_ALPHA:
+            case self::PARAM_ALPHA:
                 // Remove everything not `a-z`.
                 return preg_replace('/[^a-zA-Z]/i', '', $param);
 
-            case PARAM_ALPHAEXT:
+            case self::PARAM_ALPHAEXT:
                 // Remove everything not `a-zA-Z_-` (originally allowed "/" too).
                 return preg_replace('/[^a-zA-Z_-]/i', '', $param);
 
-            case PARAM_ALPHANUM:
+            case self::PARAM_ALPHANUM:
                 // Remove everything not `a-zA-Z0-9`.
                 return preg_replace('/[^A-Za-z0-9]/i', '', $param);
 
-            case PARAM_ALPHANUMEXT:
+            case self::PARAM_ALPHANUMEXT:
                 // Remove everything not `a-zA-Z0-9_-`.
                 return preg_replace('/[^A-Za-z0-9_-]/i', '', $param);
 
-            case PARAM_SEQUENCE:
+            case self::PARAM_SEQUENCE:
                 // Remove everything not `0-9,`.
                 return preg_replace('/[^0-9,]/i', '', $param);
 
-            case PARAM_BOOL:
+            case self::PARAM_BOOL:
                 // Convert to 1 or 0.
                 $tempstr = strtolower($param);
                 if ($tempstr === 'on' or $tempstr === 'yes' or $tempstr === 'true') {
@@ -177,12 +196,12 @@ class Request{
                 }
                 return $param;
 
-            case PARAM_NOTAGS:
+            case self::PARAM_NOTAGS:
                 // Strip all tags.
                 $param = fix_utf8($param);
                 return strip_tags($param);
 
-            case PARAM_TEXT:
+            case self::PARAM_TEXT:
                 // Leave only tags needed for multilang.
                 $param = fix_utf8($param);
                 // If the multilang syntax is not correct we strip all tags because it would break xhtml strict which is required
@@ -246,7 +265,7 @@ class Request{
                 // Easy, just strip all tags, if we ever want to fix orphaned '&' we have to do that in format_string().
                 return strip_tags($param);
 
-            case PARAM_COMPONENT:
+            case self::PARAM_COMPONENT:
                 // We do not want any guessing here, either the name is correct or not
                 // please note only normalised component names are accepted.
                 if (!preg_match('/^[a-z]+(_[a-z][a-z0-9_]*)?[a-z0-9]+$/', $param)) {
@@ -264,15 +283,15 @@ class Request{
                 return $param;
 
 
-            case PARAM_SAFEDIR:
+            case self::PARAM_SAFEDIR:
                 // Remove everything not a-zA-Z0-9_- .
                 return preg_replace('/[^a-zA-Z0-9_-]/i', '', $param);
 
-            case PARAM_SAFEPATH:
+            case self::PARAM_SAFEPATH:
                 // Remove everything not a-zA-Z0-9/_- .
                 return preg_replace('/[^a-zA-Z0-9\/_-]/i', '', $param);
 
-            case PARAM_FILE:
+            case self::PARAM_FILE:
                 // Strip all suspicious characters from filename.
                 $param = fix_utf8($param);
                 $param = preg_replace('~[[:cntrl:]]|[&<>"`\|\':\\\\/]~u', '', $param);
@@ -281,7 +300,7 @@ class Request{
                 }
                 return $param;
 
-            case PARAM_PATH:
+            case self::PARAM_PATH:
                 // Strip all suspicious characters from file path.
                 $param = fix_utf8($param);
                 $param = str_replace('\\', '/', $param);
@@ -303,7 +322,7 @@ class Request{
                 $param = preg_replace('~/(\./)+~', '/', $param);
                 return $param;
 
-            case PARAM_HOST:
+            case self::PARAM_HOST:
                 // Allow FQDN or IPv4 dotted quad.
                 $param = preg_replace('/[^\.\d\w-]/', '', $param );
                 // Match ipv4 dotted quad.
@@ -317,8 +336,8 @@ class Request{
                         $param = '';
                     }
                 } else if ( preg_match('/^[\w\d\.-]+$/', $param) // Dots, hyphens, numbers.
-                    && !preg_match('/^[\.-]/',  $param) // No leading dots/hyphens.
-                    && !preg_match('/[\.-]$/',  $param) // No trailing dots/hyphens.
+                    && !preg_match('/^[\.-]/',$param) // No leading dots/hyphens.
+                    && !preg_match('/[\.-]$/',$param) // No trailing dots/hyphens.
                 ) {
                     // All is ok - $param is respected.
                 } else {
@@ -327,7 +346,7 @@ class Request{
                 }
                 return $param;
 
-            case PARAM_URL:          // Allow safe ftp, http, mailto urls.
+            case self::PARAM_URL:          // Allow safe ftp, http, mailto urls.
                 $param = fix_utf8($param);
                 if (!empty($param) && self::validateUrlSyntax($param, 's?H?S?F?E?u-P-a?I?p?f?q?r?')) {
                     // All is ok, param is respected.
@@ -338,7 +357,7 @@ class Request{
                 return $param;
 
 
-            case PARAM_PEM:
+            case self::PARAM_PEM:
                 $param = trim($param);
                 // PEM formatted strings may contain letters/numbers and the symbols:
                 //   forward slash: /
@@ -357,7 +376,7 @@ class Request{
                 }
                 return '';
 
-            case PARAM_BASE64:
+            case self::PARAM_BASE64:
                 if (!empty($param)) {
                     // PEM formatted strings may contain letters/numbers and the symbols
                     //   forward slash: /
@@ -386,7 +405,7 @@ class Request{
                     return '';
                 }
 
-            case PARAM_TAGLIST:
+            case self::PARAM_TAGLIST:
                 $param = fix_utf8($param);
                 $tags = explode(',', $param);
                 $result = array();
@@ -402,15 +421,7 @@ class Request{
                     return '';
                 }
 
-
-
-
-
-
-
-
-
-            case PARAM_USERNAME:
+            case self::PARAM_USERNAME:
                 $param = fix_utf8($param);
                 $param = trim($param);
                 // Convert uppercase to lowercase MDL-16919.
@@ -423,7 +434,7 @@ class Request{
                 }
                 return $param;
 
-            case PARAM_EMAIL:
+            case self::PARAM_EMAIL:
                 $param = fix_utf8($param);
                 if (validate_email($param)) {
                     return $param;
@@ -431,14 +442,14 @@ class Request{
                     return '';
                 }
 
-            case PARAM_STRINGID:
+            case self::PARAM_STRINGID:
                 if (preg_match('|^[a-zA-Z][a-zA-Z0-9\.:/_-]*$|', $param)) {
                     return $param;
                 } else {
                     return '';
                 }
 
-            case PARAM_TIMEZONE:
+            case self::PARAM_TIMEZONE:
                 // Can be int, float(with .5 or .0) or string seperated by '/' and can have '-_'.
                 $param = fix_utf8($param);
                 $timezonepattern = '/^(([+-]?(0?[0-9](\.[5|0])?|1[0-3](\.0)?|1[0-2]\.5))|(99)|[[:alnum:]]+(\/?[[:alpha:]_-])+)$/';
@@ -510,13 +521,6 @@ class Request{
         }
     }
 
-    /**
-     * Validations
-     * @param $urladdr
-     * @param string $options
-     * @return bool
-     */
-
     function validateUrlSyntax( $urladdr, $options="" ){
 
         // Force Options parameter to be lower case