BasicTableHeaderUI (Java SE 25 & JDK 25)
Description: declaration: module: java.desktop, package: javax.swing.plaf.basic, class: BasicTableHeaderUI
Keywords: javax.swing.plaf.basic.BasicTableHeaderUI class

# Class BasicTableHeaderUI

java.lang.Object
javax.swing.plaf.ComponentUI
javax.swing.plaf.TableHeaderUI
javax.swing.plaf.basic.BasicTableHeaderUI

Direct Known Subclasses:
  `SynthTableHeaderUI`

public class BasicTableHeaderUI extends TableHeaderUI
BasicTableHeaderUI implementation

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `class`
  `BasicTableHeaderUI.MouseInputHandler`
  This class should be treated as a "protected" inner class.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected JTableHeader`
  `header`
  The `JTableHeader` that is delegating the painting to this UI.
  `protected MouseInputListener`
  `mouseInputListener`
  Listeners that are attached to the `JTable`
  `protected CellRendererPane`
  `rendererPane`
  The instance of `CellRendererPane`.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `BasicTableHeaderUI()`
  Constructs a `BasicTableHeaderUI`.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `protected MouseInputListener`
  `createMouseInputListener()`
  Creates the mouse listener for the `JTableHeader`.
  `static ComponentUI`
  `createUI(JComponent h)`
  Returns a new instance of `BasicTableHeaderUI`.
  `int`
  `getBaseline(JComponent c, int width, int height)`
  Returns the baseline.
  `Dimension`
  `getMaximumSize(JComponent c)`
  Return the maximum size of the header.
  `Dimension`
  `getMinimumSize(JComponent c)`
  Return the minimum size of the header.
  `Dimension`
  `getPreferredSize(JComponent c)`
  Return the preferred size of the header.
  `protected int`
  `getRolloverColumn()`
  Returns the index of the column header over which the mouse currently is.
  `protected void`
  `installDefaults()`
  Initializes JTableHeader properties such as font, foreground, and background.
  `protected void`
  `installKeyboardActions()`
  Register all keyboard actions on the JTableHeader.
  `protected void`
  `installListeners()`
  Attaches listeners to the JTableHeader.
  `protected void`
  `rolloverColumnUpdated(int oldColumn, int newColumn)`
  This method gets called every time when a rollover column in the table header is updated.
  `protected void`
  `uninstallDefaults()`
  Uninstalls default properties
  `protected void`
  `uninstallKeyboardActions()`
  Unregisters default key actions.
  `protected void`
  `uninstallListeners()`
  Unregisters listeners.

  ### Methods declared in class ComponentUI

  `contains, getAccessibleChild, getAccessibleChildrenCount, getBaselineResizeBehavior, installUI, paint, uninstallUI, update`

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### header

    protected JTableHeader header
    The `JTableHeader` that is delegating the painting to this UI.

  - ### rendererPane

    protected CellRendererPane rendererPane
    The instance of `CellRendererPane`.

  - ### mouseInputListener

    protected MouseInputListener mouseInputListener
    Listeners that are attached to the `JTable`

- ## Constructor Details

  - ### BasicTableHeaderUI

    public BasicTableHeaderUI()
    Constructs a `BasicTableHeaderUI`.

- ## Method Details

  - ### createMouseInputListener

    protected MouseInputListener createMouseInputListener()
    Creates the mouse listener for the `JTableHeader`.
    Returns:
      the mouse listener for the `JTableHeader`

  - ### createUI

    public static ComponentUI createUI(JComponent h)
    Returns a new instance of `BasicTableHeaderUI`.
    Parameters:
      `h` - a component.
    Returns:
      a new instance of `BasicTableHeaderUI`

  - ### installDefaults

    protected void installDefaults()
    Initializes JTableHeader properties such as font, foreground, and background. The font, foreground, and background properties are only set if their current value is either null or a UIResource, other properties are set if the current value is null.
    See Also:
      - `ComponentUI.installUI(JComponent)`

  - ### installListeners

    protected void installListeners()
    Attaches listeners to the JTableHeader.

  - ### installKeyboardActions

    protected void installKeyboardActions()
    Register all keyboard actions on the JTableHeader.

  - ### uninstallDefaults

    protected void uninstallDefaults()
    Uninstalls default properties

  - ### uninstallListeners

    protected void uninstallListeners()
    Unregisters listeners.

  - ### uninstallKeyboardActions

    protected void uninstallKeyboardActions()
    Unregisters default key actions.

  - ### getRolloverColumn

    protected int getRolloverColumn()
    Returns the index of the column header over which the mouse currently is. When the mouse is not over the table header, -1 is returned.
    Returns:
      the index of the current rollover column
    Since:
      1.6
    See Also:
      - `rolloverColumnUpdated(int, int)`

  - ### rolloverColumnUpdated

    protected void rolloverColumnUpdated(int oldColumn, int newColumn)
    This method gets called every time when a rollover column in the table header is updated. Every look and feel that supports a rollover effect in a table header should override this method and repaint the header.
    Parameters:
      `oldColumn` - the index of the previous rollover column or -1 if the mouse was not over a column
      `newColumn` - the index of the new rollover column or -1 if the mouse is not over a column
    Since:
      1.6
    See Also:
      - `getRolloverColumn()`
      - `JTableHeader.getHeaderRect(int)`

  - ### getBaseline

    public int getBaseline(JComponent c, int width, int height)
    Returns the baseline.
    Overrides:
      `getBaseline` in class `ComponentUI`
    Parameters:
      `c` - `JComponent` baseline is being requested for
      `width` - the width to get the baseline for
      `height` - the height to get the baseline for
    Returns:
      baseline or a value < 0 indicating there is no reasonable baseline
    Throws:
      `NullPointerException` - if `c` is `null`
      `IllegalArgumentException` - if width or height is < 0
    Since:
      1.6
    See Also:
      - `JComponent.getBaseline(int, int)`

  - ### getMinimumSize

    public Dimension getMinimumSize(JComponent c)
    Return the minimum size of the header. The minimum width is the sum of the minimum widths of each column (plus inter-cell spacing).
    Overrides:
      `getMinimumSize` in class `ComponentUI`
    Parameters:
      `c` - the component whose minimum size is being queried; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components
    Returns:
      a `Dimension` object or `null`
    See Also:
      - `JComponent.getMinimumSize()`
      - `LayoutManager.minimumLayoutSize(Container)`
      - `ComponentUI.getPreferredSize(JComponent)`

  - ### getPreferredSize

    public Dimension getPreferredSize(JComponent c)
    Return the preferred size of the header. The preferred height is the maximum of the preferred heights of all of the components provided by the header renderers. The preferred width is the sum of the preferred widths of each column (plus inter-cell spacing).
    Overrides:
      `getPreferredSize` in class `ComponentUI`
    Parameters:
      `c` - the component whose preferred size is being queried; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components
    Returns:
      a `Dimension` object containing given component's preferred size appropriate for the look and feel
    See Also:
      - `JComponent.getPreferredSize()`
      - `LayoutManager.preferredLayoutSize(Container)`

  - ### getMaximumSize

    public Dimension getMaximumSize(JComponent c)
    Return the maximum size of the header. The maximum width is the sum of the maximum widths of each column (plus inter-cell spacing).
    Overrides:
      `getMaximumSize` in class `ComponentUI`
    Parameters:
      `c` - the component whose maximum size is being queried; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components
    Returns:
      a `Dimension` object or `null`
    See Also:
      - `JComponent.getMaximumSize()`
      - `LayoutManager2.maximumLayoutSize(Container)`