如何支持辅助技术

JButton button = new JButton("我是一个Swing按钮！");
label = new JLabel(labelPrefix + "0    ");
label.setText(labelPrefix + numClicks);
JFrame frame = new JFrame("SwingApplication");

public AccessibleScrollDemo() {
    // 获取要使用的图片。
    ImageIcon bee = createImageIcon("images/flyingBee.jpg",
                      "一只飞行的蜜蜂的照片。");

    // 创建行和列的标题。
    columnView = new Rule(Rule.HORIZONTAL, true);
    if (bee != null) {
        columnView.setPreferredWidth(bee.getIconWidth());
    } else {
        columnView.setPreferredWidth(320);
    }
    columnView.getAccessibleContext().setAccessibleName("列标题");
    columnView.getAccessibleContext().
            setAccessibleDescription("显示用于测量滚动窗格客户端的水平标尺。");
    rowView = new Rule(Rule.VERTICAL, true);
    if (bee != null) {
        rowView.setPreferredHeight(bee.getIconHeight());
    } else {
        rowView.setPreferredHeight(480);
    }
    rowView.getAccessibleContext().setAccessibleName("行标题");
    rowView.getAccessibleContext().
            setAccessibleDescription("显示用于测量滚动窗格客户端的垂直标尺。");

    // 创建角落。
    JPanel buttonCorner = new JPanel();
    isMetric = new JToggleButton("cm", true);
    isMetric.setFont(new Font("SansSerif", Font.PLAIN, 11));
    isMetric.setMargin(new Insets(2,2,2,2));
    isMetric.addItemListener(this);
    isMetric.setToolTipText("在英寸和厘米之间切换标尺的单位。");
    buttonCorner.add(isMetric); //使用默认的FlowLayout
    buttonCorner.getAccessibleContext().
                 setAccessibleName("左上角");

    String desc = "出于美观原因，用颜色填充滚动窗格的角落。";
    Corner lowerLeft = new Corner();
    lowerLeft.getAccessibleContext().
              setAccessibleName("左下角");
    lowerLeft.getAccessibleContext().setAccessibleDescription(desc);

    Corner upperRight = new Corner();
    upperRight.getAccessibleContext().
               setAccessibleName("右上角");
    upperRight.getAccessibleContext().setAccessibleDescription(desc);
    
    // 设置滚动窗格。
    picture = new ScrollablePicture(bee,
                                    columnView.getIncrement());
    picture.setToolTipText(bee.getDescription());
    picture.getAccessibleContext().setAccessibleName(
                                     "滚动窗格客户端");

    JScrollPane pictureScrollPane = new JScrollPane(picture);
    pictureScrollPane.setPreferredSize(new Dimension(300, 250));
    pictureScrollPane.setViewportBorder(
            BorderFactory.createLineBorder(Color.black));

    pictureScrollPane.setColumnHeaderView(columnView);
    pictureScrollPane.setRowHeaderView(rowView);

    // 理论上，为了支持国际化，你应该将UPPER_LEFT_CORNER更改为UPPER_LEADING_CORNER，
    // LOWER_LEFT_CORNER更改为LOWER_LEADING_CORNER，以及
    // UPPER_RIGHT_CORNER更改为UPPER_TRAILING_CORNER。但是，在实践中，
    // bug #4467063使得这是不可能的（至少在1.4.0中）。
    pictureScrollPane.setCorner(JScrollPane.UPPER_LEFT_CORNER,
                                buttonCorner);
    pictureScrollPane.setCorner(JScrollPane.LOWER_LEFT_CORNER,
                                lowerLeft);
    pictureScrollPane.setCorner(JScrollPane.UPPER_RIGHT_CORNER,
                                upperRight);

    // 将其放在此面板中。
    setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
    add(pictureScrollPane);
    setBorder(BorderFactory.createEmptyBorder(20,20,20,20));
}

Component.AccessibleComponent

public class Corner extends JComponent implements Accessible {

    protected void paintComponent(Graphics g) {
        //使用脏棕橙色进行填充。
        g.setColor(new Color(230, 163, 4));
        g.fillRect(0, 0, getWidth(), getHeight());
    }

    public AccessibleContext getAccessibleContext() {
        if (accessibleContext == null) {
            accessibleContext = new AccessibleCorner();
        }
        return accessibleContext;
    }

    protected class AccessibleCorner extends AccessibleJComponent {
        //继承所有内容，不进行任何重写。
    }
}

protected class AccessibleRuler extends AccessibleJComponent {

    public AccessibleRole getAccessibleRole() {
        return AccessibleRuleRole.RULER;
    }

    public AccessibleStateSet getAccessibleStateSet() {
        AccessibleStateSet states =
            super.getAccessibleStateSet();
        if (orientation == VERTICAL) {
            states.add(AccessibleState.VERTICAL);
        } else {
            states.add(AccessibleState.HORIZONTAL);
        }
        if (isMetric) {
            states.add(AccessibleRulerState.CENTIMETERS);
        } else {
            states.add(AccessibleRulerState.INCHES);
        }
        return states;
    }
}

class AccessibleRuleRole extends AccessibleRole {
    public static final AccessibleRuleRole RULER
        = new AccessibleRuleRole("ruler");

    protected AccessibleRuleRole(String key) {
        super(key);
    }

    //实际上应该提供这些名称的本地化版本。
    public String toDisplayString(String resourceBundleName,
                                  Locale locale) {
        return key;
    }
}

class AccessibleRulerState extends AccessibleState {
    public static final AccessibleRulerState INCHES
        = new AccessibleRulerState("inches");
    public static final AccessibleRulerState CENTIMETERS
        = new AccessibleRulerState("centimeters");

    protected AccessibleRulerState(String key) {
        super(key);
    }

    //实际上应该提供这些名称的本地化版本。
    public String toDisplayString(String resourceBundleName,
                                  Locale locale) {
        return key;
    }
}