Define access modifier for functions

~dev_rating/application/classes/Model/Helper/StudentBuilder.php

@@ -20,49 +20,49 @@ class Model_Helper_StudentBuilder extends Model_Helper_Builder
         return new Model_Student($this->data, false);
     }
 
-    function & lastName($string) {
+    public function & lastName($string) {
         $string = trim($string);  # todo: remove empty symbols
-        if (!strlen($string))
+        if (!$string)
             throw new InvalidArgumentException('Last name can\'t be empty');
         $this->data['LastName'] = $string;
         return $this;
     }
 
-    function & firstName($string) {
+    public function & firstName($string) {
         $string = trim($string);
-        if (!strlen($string))
+        if (!$string)
             throw new InvalidArgumentException('First name can\'t be empty');
         $this->data['FirstName'] = $string;
         return $this;
     }
 
-    function & secondName($string) {
+    public function & secondName($string) {
         $this->data['SecondName'] = trim($string);
         return $this;
     }
 
-    function & grade($id) {
+    public function & grade($id) {
         if (!is_numeric($id) || $id <= 0)
             throw new InvalidArgumentException('Grade id is incorrect');
         $this->data['GradeID'] = (int) $id;
         return $this;
     }
 
-    function & group($num) {
+    public function & group($num) {
         if (!is_numeric($num) || $num <= 0)
             throw new InvalidArgumentException('GroupNum id is incorrect');
         $this->data['GroupNum'] = (int) $num;
         return $this;
     }
 
-    function & faculty($id) {
+    public function & faculty($id) {
         if (!is_numeric($id) || $id <= 0)
             throw new InvalidArgumentException('Faculty id is incorrect');
         $this->data['FacultyID'] = (int) $id;
         return $this;
     }
 
-    function & semester($id) {
+    public function & semester($id) {
         if (!is_numeric($id) || $id <= 0)
             throw new InvalidArgumentException('Semester id is incorrect');
         $this->data['SemesterID'] = (int) $id;