private void addButtons() {
		JPanel buttonHolder = new JPanel();
		buttonHolder.setLayout(new BoxLayout(buttonHolder, BoxLayout.X_AXIS));
		JButton process = new JButton("Create map");
		final Gui gui = this;
		process.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				if (!mapData.getSelectedFile().exists()
						|| !styleChooser.getSelectedFile().exists()) {
					JOptionPane.showMessageDialog(gui,
							"You need to select map data and a stylesheet.");
					return;
				}
				if (!target.getSelectedFile().canWrite()) {
					JOptionPane.showMessageDialog(gui,
							"Target file is not writeable");
					return;
				} else {
					int overwrite = JOptionPane.showConfirmDialog(gui,
							"Overwrite the target file?", "",
							JOptionPane.YES_NO_OPTION);
					if (overwrite != JOptionPane.YES_OPTION) {
						return;
					}
				}
				ProcessMap processMap = new ProcessMap();
				processMap.setMapData(mapData.getSelectedFile());
				processMap.setStyleFile(styleChooser.getSelectedFile());
				try {
					processMap.createMap();
				} catch (Exception e1) {
					JOptionPane.showMessageDialog(gui,
							"Could not generate map (see console for details): "
									+ e1.getMessage());
					e1.printStackTrace();
				}
			}
		});
		buttonHolder.add(process);
		buttonHolder.add(new JButton("Create & display map"));
		this.add(buttonHolder);
	}