程序代码：

    public JButton[] createButtons(){
        String[] label = {"1","2","3","+","4","5","6","-","7","8","9","*","0","/",".","="};
        JButton[] buttons = new JButton[16];
        for(int i=0;i<label.length;i++){
            buttons[i] = new JButton(label[i]);
        }
        return buttons;
    }