Javascript calling public function in a private function in a class

Exactly like the title, here is a demo of Javascript calling public function in a private function in a class.

var hello = function()
{
	this.hey = function(){ console.log("hey"); }

	var _this = this; // store this(the hello class) to _this
	var init = function init()
	{
		_this.hey(); // If use this here, it will throw error, because this here refers to the window context
	}
	
	init();
}
var h = new hello();