JButton.getUI method would return an instance of MultiButtonUI, which would handle both a MotifButtonUI and an AudioButtonUI. For more information, see Using the Multiplexing Look and Feel.
Note: Most of the Swing API is not thread safe. For details, see Concurrency in Swing, a section in The Java Tutorial.
| Class | Description | 
|---|---|
| MultiButtonUI | A multiplexing UI used to combine  ButtonUIs. | 
| MultiColorChooserUI | A multiplexing UI used to combine  ColorChooserUIs. | 
| MultiComboBoxUI | A multiplexing UI used to combine  ComboBoxUIs. | 
| MultiDesktopIconUI | A multiplexing UI used to combine  DesktopIconUIs. | 
| MultiDesktopPaneUI | A multiplexing UI used to combine  DesktopPaneUIs. | 
| MultiFileChooserUI | A multiplexing UI used to combine  FileChooserUIs. | 
| MultiInternalFrameUI | A multiplexing UI used to combine  InternalFrameUIs. | 
| MultiLabelUI | A multiplexing UI used to combine  LabelUIs. | 
| MultiListUI | A multiplexing UI used to combine  ListUIs. | 
| MultiLookAndFeel | A multiplexing look and feel that allows more than one UI to be associated with a component at the same time. | 
| MultiMenuBarUI | A multiplexing UI used to combine  MenuBarUIs. | 
| MultiMenuItemUI | A multiplexing UI used to combine  MenuItemUIs. | 
| MultiOptionPaneUI | A multiplexing UI used to combine  OptionPaneUIs. | 
| MultiPanelUI | A multiplexing UI used to combine  PanelUIs. | 
| MultiPopupMenuUI | A multiplexing UI used to combine  PopupMenuUIs. | 
| MultiProgressBarUI | A multiplexing UI used to combine  ProgressBarUIs. | 
| MultiRootPaneUI | A multiplexing UI used to combine  RootPaneUIs. | 
| MultiScrollBarUI | A multiplexing UI used to combine  ScrollBarUIs. | 
| MultiScrollPaneUI | A multiplexing UI used to combine  ScrollPaneUIs. | 
| MultiSeparatorUI | A multiplexing UI used to combine  SeparatorUIs. | 
| MultiSliderUI | A multiplexing UI used to combine  SliderUIs. | 
| MultiSpinnerUI | A multiplexing UI used to combine  SpinnerUIs. | 
| MultiSplitPaneUI | A multiplexing UI used to combine  SplitPaneUIs. | 
| MultiTabbedPaneUI | A multiplexing UI used to combine  TabbedPaneUIs. | 
| MultiTableHeaderUI | A multiplexing UI used to combine  TableHeaderUIs. | 
| MultiTableUI | A multiplexing UI used to combine  TableUIs. | 
| MultiTextUI | A multiplexing UI used to combine  TextUIs. | 
| MultiToolBarUI | A multiplexing UI used to combine  ToolBarUIs. | 
| MultiToolTipUI | A multiplexing UI used to combine  ToolTipUIs. | 
| MultiTreeUI | A multiplexing UI used to combine  TreeUIs. | 
| MultiViewportUI | A multiplexing UI used to combine  ViewportUIs. | 
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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    https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/javax/swing/plaf/multi/package-summary.html