resolveActionMethodName() protected method

Resolves and checks the current action method name
protected resolveActionMethodName ( ) : string
return string Method name of the current action
 /**
  * Determines the action method and assures that the method exists.
  *
  * @return string The action method name
  * @throws NoSuchActionException if the action specified in the request object does not exist (and if there's no default action either).
  */
 protected function resolveActionMethodName()
 {
     if ($this->request->getControllerActionName() === 'index') {
         $actionName = 'index';
         switch ($this->request->getHttpRequest()->getMethod()) {
             case 'HEAD':
             case 'GET':
                 $actionName = $this->request->hasArgument($this->resourceArgumentName) ? 'show' : 'list';
                 break;
             case 'POST':
                 $actionName = 'create';
                 break;
             case 'PUT':
                 if (!$this->request->hasArgument($this->resourceArgumentName)) {
                     $this->throwStatus(400, null, 'No resource specified');
                 }
                 $actionName = 'update';
                 break;
             case 'DELETE':
                 if (!$this->request->hasArgument($this->resourceArgumentName)) {
                     $this->throwStatus(400, null, 'No resource specified');
                 }
                 $actionName = 'delete';
                 break;
         }
         $this->request->setControllerActionName($actionName);
     }
     return parent::resolveActionMethodName();
 }