How can I find out that a Node or a ButtonBase is a Button?

The title says it. How can I check that a

Node item or a ButtonBase Item is a Button? Can I use the equalsmethode?

public void initListener(ArrayList<TreeItem> treeBranches, ButtonBase item){
        readXML.setOnAction(new EventHandler<ActionEvent>() {
            ...
        });

        if(treeBranches != null){
            ....
        }

        if(item != null && **item.equals**....?)){

        }