The code which you have given here is only responsible for putting focus on inputtext.But you want to place cursor at end of the input text for this you have to some write more java script.
Link is following
BTW you can find more example on google.
the ADF Faces component.focus() method does not give you access to the field value. If this is your requirement then you need to lookup it1::content to get access the the actual HTML field. Then you set the focus using the DOM focus() method