public scrollpanel() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 376, 458);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);
        contentPane.setLayout(null);
        
        JScrollPane scrollPane = new JScrollPane();
        scrollPane.setEnabled(false);
        scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
        scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
        scrollPane.setBounds(5, 5, 300, 400);
        scrollPane.setSize(300, 400);
        contentPane.add(scrollPane);
        
            
        JPanel panel = new JPanel();
        panel.setBounds(1,1,200,200);
        scrollPane.setViewportView(panel);
            panel.setLayout(null);
                 
        for(int i =0 ;i<150;i++){
                         JButton j = new JButton();
                         j.setBounds( 0,i*100,100, 100);
              panel.add(j);
            }   
    }