# Class BasicComboPopup

java.lang.Object
java.awt.Component
java.awt.Container
javax.swing.JComponent
javax.swing.JPopupMenu
javax.swing.plaf.basic.BasicComboPopup

All Implemented Interfaces:
  `ImageObserver, MenuContainer, Serializable, Accessible, MenuElement, ComboPopup`

Direct Known Subclasses:
  `MetalComboBoxUI.MetalComboPopup`

public class BasicComboPopup extends JPopupMenu implements ComboPopup
This is a basic implementation of the `ComboPopup` interface. This class represents the ui for the popup portion of the combo box.

All event handling is handled by listener classes created with the `createxxxListener()` methods and internal classes. You can change the behavior of this class by overriding the `createxxxListener()` methods and supplying your own event listeners or subclassing from the ones supplied in this class.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans has been added to the `java.beans` package. Please see `XMLEncoder`.

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `class`
  `BasicComboPopup.InvocationKeyHandler`
  As of Java 2 platform v 1.4, this class is now obsolete and is only included for backwards API compatibility.
  `protected class`
  `BasicComboPopup.InvocationMouseHandler`
  A listener to be registered upon the combo box (not its popup menu) to handle mouse events that affect the state of the popup menu.
  `protected class`
  `BasicComboPopup.InvocationMouseMotionHandler`
  This listener watches for dragging and updates the current selection in the list if it is dragging over the list.
  `protected class`
  `BasicComboPopup.ItemHandler`
  This listener watches for changes to the selection in the combo box.
  `class`
  `BasicComboPopup.ListDataHandler`
  As of 1.4, this class is now obsolete, doesn't do anything, and is only included for backwards API compatibility.
  `protected class`
  `BasicComboPopup.ListMouseHandler`
  This listener hides the popup when the mouse is released in the list.
  `protected class`
  `BasicComboPopup.ListMouseMotionHandler`
  This listener changes the selected item as you move the mouse over the list.
  `protected class`
  `BasicComboPopup.ListSelectionHandler`
  As of Java 2 platform v 1.4, this class is now obsolete, doesn't do anything, and is only included for backwards API compatibility.
  `protected class`
  `BasicComboPopup.PropertyChangeHandler`
  This listener watches for bound properties that have changed in the combo box.

  ### Nested classes/interfaces declared in class JPopupMenu

  `JPopupMenu.AccessibleJPopupMenu, JPopupMenu.Separator`
  Modifier and Type
  Class
  Description
  `protected class`
  `JPopupMenu.AccessibleJPopupMenu`
  This class implements accessibility support for the `JPopupMenu` class.
  `static class`
  `JPopupMenu.Separator`
  A popup menu-specific separator.

  ### Nested classes/interfaces declared in class JComponent

  `JComponent.AccessibleJComponent`
  Modifier and Type
  Class
  Description
  `class`
  `JComponent.AccessibleJComponent`
  Inner class of JComponent used to provide default support for accessibility.

  ### Nested classes/interfaces declared in class Container

  `Container.AccessibleAWTContainer`
  Modifier and Type
  Class
  Description
  `protected class`
  `Container.AccessibleAWTContainer`
  Inner class of Container used to provide default support for accessibility.

  ### Nested classes/interfaces declared in class Component

  `Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy`
  Modifier and Type
  Class
  Description
  `protected class`
  `Component.AccessibleAWTComponent`
  Inner class of Component used to provide default support for accessibility.
  `static enum`
  `Component.BaselineResizeBehavior`
  Enumeration of the common ways the baseline of a component can change as the size changes.
  `protected class`
  `Component.BltBufferStrategy`
  Inner class for blitting offscreen surfaces to a component.
  `protected class`
  `Component.FlipBufferStrategy`
  Inner class for flipping buffers on a component.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected Timer`
  `autoscrollTimer`
  This protected field is implementation specific.
  `protected JComboBox<Object>`
  `comboBox`
  The instance of `JComboBox`.
  `protected boolean`
  `hasEntered`
  `true` if the mouse cursor is in the popup.
  `protected boolean`
  `isAutoScrolling`
  If `true` the auto-scrolling is enabled.
  `protected ItemListener`
  `itemListener`
  This protected field is implementation specific.
  `protected KeyListener`
  `keyListener`
  This protected field is implementation specific.
  `protected JList<Object>`
  `list`
  This protected field is implementation specific.
  `protected ListDataListener`
  `listDataListener`
  This protected field is implementation specific.
  `protected MouseListener`
  `listMouseListener`
  This protected field is implementation specific.
  `protected MouseMotionListener`
  `listMouseMotionListener`
  This protected field is implementation specific.
  `protected ListSelectionListener`
  `listSelectionListener`
  This protected field is implementation specific.
  `protected MouseListener`
  `mouseListener`
  This protected field is implementation specific.
  `protected MouseMotionListener`
  `mouseMotionListener`
  This protected field is implementation specific.
  `protected PropertyChangeListener`
  `propertyChangeListener`
  This protected field is implementation specific.
  `protected static final int`
  `SCROLL_DOWN`
  The direction of scrolling down.
  `protected static final int`
  `SCROLL_UP`
  The direction of scrolling up.
  `protected int`
  `scrollDirection`
  The direction of scrolling.
  `protected JScrollPane`
  `scroller`
  This protected field is implementation specific.
  `protected boolean`
  `valueIsAdjusting`
  As of Java 2 platform v1.4 this previously undocumented field is no longer used.

  ### Fields declared in class JComponent

  `listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW`
  Modifier and Type
  Field
  Description
  `protected EventListenerList`
  `listenerList`
  A list of event listeners for this component.
  `static final String`
  `TOOL_TIP_TEXT_KEY`
  The comment to display when the cursor is over the component, also known as a "value tip", "flyover help", or "flyover label".
  `protected ComponentUI`
  `ui`
  The look and feel delegate for this component.
  `static final int`
  `UNDEFINED_CONDITION`
  Constant used by some of the APIs to mean that no condition is defined.
  `static final int`
  `WHEN_ANCESTOR_OF_FOCUSED_COMPONENT`
  Constant used for `registerKeyboardAction` that means that the command should be invoked when the receiving component is an ancestor of the focused component or is itself the focused component.
  `static final int`
  `WHEN_FOCUSED`
  Constant used for `registerKeyboardAction` that means that the command should be invoked when the component has the focus.
  `static final int`
  `WHEN_IN_FOCUSED_WINDOW`
  Constant used for `registerKeyboardAction` that means that the command should be invoked when the receiving component is in the window that has the focus or is itself the focused component.

  ### Fields declared in class Component

  `accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT`
  Modifier and Type
  Field
  Description
  `protected AccessibleContext`
  `accessibleContext`
  The `AccessibleContext` associated with this `Component`.
  `static final float`
  `BOTTOM_ALIGNMENT`
  Ease-of-use constant for `getAlignmentY`.
  `static final float`
  `CENTER_ALIGNMENT`
  Ease-of-use constant for `getAlignmentY` and `getAlignmentX`.
  `static final float`
  `LEFT_ALIGNMENT`
  Ease-of-use constant for `getAlignmentX`.
  `static final float`
  `RIGHT_ALIGNMENT`
  Ease-of-use constant for `getAlignmentX`.
  `static final float`
  `TOP_ALIGNMENT`
  Ease-of-use constant for `getAlignmentY()`.

  ### Fields declared in interface ImageObserver

  `ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH`
  Modifier and Type
  Field
  Description
  `static final int`
  `ABORT`
  This flag in the infoflags argument to imageUpdate indicates that an image which was being tracked asynchronously was aborted before production was complete.
  `static final int`
  `ALLBITS`
  This flag in the infoflags argument to imageUpdate indicates that a static image which was previously drawn is now complete and can be drawn again in its final form.
  `static final int`
  `ERROR`
  This flag in the infoflags argument to imageUpdate indicates that an image which was being tracked asynchronously has encountered an error.
  `static final int`
  `FRAMEBITS`
  This flag in the infoflags argument to imageUpdate indicates that another complete frame of a multi-frame image which was previously drawn is now available to be drawn again.
  `static final int`
  `HEIGHT`
  This flag in the infoflags argument to imageUpdate indicates that the height of the base image is now available and can be taken from the height argument to the imageUpdate callback method.
  `static final int`
  `PROPERTIES`
  This flag in the infoflags argument to imageUpdate indicates that the properties of the image are now available.
  `static final int`
  `SOMEBITS`
  This flag in the infoflags argument to imageUpdate indicates that more pixels needed for drawing a scaled variation of the image are available.
  `static final int`
  `WIDTH`
  This flag in the infoflags argument to imageUpdate indicates that the width of the base image is now available and can be taken from the width argument to the imageUpdate callback method.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `BasicComboPopup(JComboBox<Object> combo)`
  Constructs a new instance of `BasicComboPopup`.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `protected void`
  `autoScrollDown()`
  This protected method is implementation specific and should be private. do not call or override.
  `protected void`
  `autoScrollUp()`
  This protected method is implementation specific and should be private. do not call or override.
  `protected Rectangle`
  `computePopupBounds(int px, int py, int pw, int ph)`
  Calculate the placement and size of the popup portion of the combo box based on the combo box location and the enclosing screen bounds.
  `protected void`
  `configureList()`
  Configures the list which is used to hold the combo box items in the popup.
  `protected void`
  `configurePopup()`
  Configures the popup portion of the combo box.
  `protected void`
  `configureScroller()`
  Configures the scrollable portion which holds the list within the combo box popup.
  `protected MouseEvent`
  `convertMouseEvent(MouseEvent e)`
  Converts mouse event.
  `protected ItemListener`
  `createItemListener()`
  Creates an `ItemListener` which will be added to the combo box.
  `protected KeyListener`
  `createKeyListener()`
  Creates the key listener that will be added to the combo box.
  `protected JList<Object>`
  `createList()`
  Creates the JList used in the popup to display the items in the combo box model.
  `protected ListDataListener`
  `createListDataListener()`
  Creates a list data listener which will be added to the `ComboBoxModel`.
  `protected MouseListener`
  `createListMouseListener()`
  Creates a mouse listener that watches for mouse events in the popup's list.
  `protected MouseMotionListener`
  `createListMouseMotionListener()`
  Creates a mouse motion listener that watches for mouse motion events in the popup's list.
  `protected ListSelectionListener`
  `createListSelectionListener()`
  Creates a list selection listener that watches for selection changes in the popup's list.
  `protected MouseListener`
  `createMouseListener()`
  Creates a listener that will watch for mouse-press and release events on the combo box.
  `protected MouseMotionListener`
  `createMouseMotionListener()`
  Creates the mouse motion listener which will be added to the combo box.
  `protected PropertyChangeListener`
  `createPropertyChangeListener()`
  Creates a `PropertyChangeListener` which will be added to the combo box.
  `protected JScrollPane`
  `createScroller()`
  Creates the scroll pane which houses the scrollable list.
  `protected void`
  `delegateFocus(MouseEvent e)`
  This is a utility method that helps event handlers figure out where to send the focus when the popup is brought up.
  `AccessibleContext`
  `getAccessibleContext()`
  Gets the AccessibleContext associated with this BasicComboPopup.
  `KeyListener`
  `getKeyListener()`
  Implementation of ComboPopup.getKeyListener().
  `JList<Object>`
  `getList()`
  Implementation of ComboPopup.getList().
  `MouseListener`
  `getMouseListener()`
  Implementation of ComboPopup.getMouseListener().
  `MouseMotionListener`
  `getMouseMotionListener()`
  Implementation of ComboPopup.getMouseMotionListener().
  `protected int`
  `getPopupHeightForRowCount(int maxRowCount)`
  Retrieves the height of the popup based on the current ListCellRenderer and the maximum row count.
  `void`
  `hide()`
  Implementation of ComboPopup.hide().
  `protected void`
  `installComboBoxListeners()`
  This method adds the necessary listeners to the JComboBox.
  `protected void`
  `installComboBoxModelListeners(ComboBoxModel<?> model)`
  Installs the listeners on the combo box model.
  `protected void`
  `installKeyboardActions()`
  Registers keyboard actions.
  `protected void`
  `installListListeners()`
  Adds the listeners to the list control.
  `boolean`
  `isFocusTraversable()`
  Overridden to unconditionally return false.
  `void`
  `show()`
  Implementation of ComboPopup.show().
  `protected void`
  `startAutoScrolling(int direction)`
  This protected method is implementation specific and should be private. do not call or override.
  `protected void`
  `stopAutoScrolling()`
  This protected method is implementation specific and should be private. do not call or override.
  `protected void`
  `togglePopup()`
  Makes the popup visible if it is hidden and makes it hidden if it is visible.
  `protected void`
  `uninstallComboBoxModelListeners(ComboBoxModel<?> model)`
  Removes the listeners from the combo box model
  `void`
  `uninstallingUI()`
  Called when the UI is uninstalling.
  `protected void`
  `uninstallKeyboardActions()`
  Unregisters keyboard actions.
  `protected void`
  `updateListBoxSelectionForEvent(MouseEvent anEvent, boolean shouldScroll)`
  A utility method used by the event listeners.

  ### Methods declared in class JPopupMenu

  `add, add, add, addMenuKeyListener, addPopupMenuListener, addSeparator, createActionChangeListener, createActionComponent, firePopupMenuCanceled, firePopupMenuWillBecomeInvisible, firePopupMenuWillBecomeVisible, getComponent, getComponentAtIndex, getComponentIndex, getDefaultLightWeightPopupEnabled, getInvoker, getLabel, getMargin, getMenuKeyListeners, getPopupMenuListeners, getSelectionModel, getSubElements, getUI, getUIClassID, insert, insert, isBorderPainted, isLightWeightPopupEnabled, isPopupTrigger, isVisible, menuSelectionChanged, pack, paintBorder, paramString, processKeyEvent, processKeyEvent, processMouseEvent, remove, removeMenuKeyListener, removePopupMenuListener, setBorderPainted, setDefaultLightWeightPopupEnabled, setInvoker, setLabel, setLightWeightPopupEnabled, setLocation, setPopupSize, setPopupSize, setSelected, setSelectionModel, setUI, setVisible, show, updateUI`
  Modifier and Type
  Method
  Description
  `JMenuItem`
  `add(String s)`
  Creates a new menu item with the specified text and appends it to the end of this menu.
  `JMenuItem`
  `add(Action a)`
  Appends a new menu item to the end of the menu which dispatches the specified `Action` object.
  `JMenuItem`
  `add(JMenuItem menuItem)`
  Appends the specified menu item to the end of this menu.
  `void`
  `addMenuKeyListener(MenuKeyListener l)`
  Adds a `MenuKeyListener` to the popup menu.
  `void`
  `addPopupMenuListener(PopupMenuListener l)`
  Adds a `PopupMenu` listener.
  `void`
  `addSeparator()`
  Appends a new separator at the end of the menu.
  `protected PropertyChangeListener`
  `createActionChangeListener(JMenuItem b)`
  Returns a properly configured `PropertyChangeListener` which updates the control as changes to the `Action` occur.
  `protected JMenuItem`
  `createActionComponent(Action a)`
  Factory method which creates the `JMenuItem` for `Actions` added to the `JPopupMenu`.
  `protected void`
  `firePopupMenuCanceled()`
  Notifies `PopupMenuListeners` that this popup menu is cancelled.
  `protected void`
  `firePopupMenuWillBecomeInvisible()`
  Notifies `PopupMenuListener`s that this popup menu will become invisible.
  `protected void`
  `firePopupMenuWillBecomeVisible()`
  Notifies `PopupMenuListener`s that this popup menu will become visible.
  `Component`
  `getComponent()`
  Returns this `JPopupMenu` component.
  `Component`
  `getComponentAtIndex(int i)`
  Deprecated.
  replaced by `Container.getComponent(int)`
  `int`
  `getComponentIndex(Component c)`
  Returns the index of the specified component.
  `static boolean`
  `getDefaultLightWeightPopupEnabled()`
  Gets the `defaultLightWeightPopupEnabled` property, which by default is `true`.
  `Component`
  `getInvoker()`
  Returns the component which is the 'invoker' of this popup menu.
  `String`
  `getLabel()`
  Returns the popup menu's label
  `Insets`
  `getMargin()`
  Returns the margin, in pixels, between the popup menu's border and its containers.
  `MenuKeyListener[]`
  `getMenuKeyListeners()`
  Returns an array of all the `MenuKeyListener`s added to this JPopupMenu with addMenuKeyListener().
  `PopupMenuListener[]`
  `getPopupMenuListeners()`
  Returns an array of all the `PopupMenuListener`s added to this JMenuItem with addPopupMenuListener().
  `SingleSelectionModel`
  `getSelectionModel()`
  Returns the model object that handles single selections.
  `MenuElement[]`
  `getSubElements()`
  Returns an array of `MenuElement`s containing the submenu for this menu component.
  `PopupMenuUI`
  `getUI()`
  Returns the look and feel (L&F) object that renders this component.
  `String`
  `getUIClassID()`
  Returns the name of the L&F class that renders this component.
  `void`
  `insert(Component component, int index)`
  Inserts the specified component into the menu at a given position.
  `void`
  `insert(Action a, int index)`
  Inserts a menu item for the specified `Action` object at a given position.
  `boolean`
  `isBorderPainted()`
  Checks whether the border should be painted.
  `boolean`
  `isLightWeightPopupEnabled()`
  Gets the `lightWeightPopupEnabled` property.
  `boolean`
  `isPopupTrigger(MouseEvent e)`
  Returns true if the `MouseEvent` is considered a popup trigger by the `JPopupMenu`'s currently installed UI.
  `boolean`
  `isVisible()`
  Returns true if the popup menu is visible (currently being displayed).
  `void`
  `menuSelectionChanged(boolean isIncluded)`
  Messaged when the menubar selection changes to activate or deactivate this menu.
  `void`
  `pack()`
  Lays out the container so that it uses the minimum space needed to display its contents.
  `protected void`
  `paintBorder(Graphics g)`
  Paints the popup menu's border if the `borderPainted` property is `true`.
  `protected String`
  `paramString()`
  Returns a string representation of this `JPopupMenu`.
  `protected void`
  `processKeyEvent(KeyEvent evt)`
  Processes key stroke events such as mnemonics and accelerators.
  `void`
  `processKeyEvent(KeyEvent e, MenuElement[] path, MenuSelectionManager manager)`
  Processes a key event forwarded from the `MenuSelectionManager` and changes the menu selection, if necessary, by using `MenuSelectionManager`'s API.
  `void`
  `processMouseEvent(MouseEvent event, MenuElement[] path, MenuSelectionManager manager)`
  This method is required to conform to the `MenuElement` interface, but it not implemented.
  `void`
  `remove(int pos)`
  Removes the component at the specified index from this popup menu.
  `void`
  `removeMenuKeyListener(MenuKeyListener l)`
  Removes a `MenuKeyListener` from the popup menu.
  `void`
  `removePopupMenuListener(PopupMenuListener l)`
  Removes a `PopupMenu` listener.
  `void`
  `setBorderPainted(boolean b)`
  Sets whether the border should be painted.
  `static void`
  `setDefaultLightWeightPopupEnabled(boolean aFlag)`
  Sets the default value of the `lightWeightPopupEnabled` property.
  `void`
  `setInvoker(Component invoker)`
  Sets the invoker of this popup menu -- the component in which the popup menu is to be displayed.
  `void`
  `setLabel(String label)`
  Sets the popup menu's label.
  `void`
  `setLightWeightPopupEnabled(boolean aFlag)`
  Sets the value of the `lightWeightPopupEnabled` property, which by default is `true`.
  `void`
  `setLocation(int x, int y)`
  Sets the location of the upper left corner of the popup menu using x, y coordinates.
  `void`
  `setPopupSize(int width, int height)`
  Sets the size of the Popup window to the specified width and height.
  `void`
  `setPopupSize(Dimension d)`
  Sets the size of the Popup window using a `Dimension` object.
  `void`
  `setSelected(Component sel)`
  Sets the currently selected component, This will result in a change to the selection model.
  `void`
  `setSelectionModel(SingleSelectionModel model)`
  Sets the model object to handle single selections.
  `void`
  `setUI(PopupMenuUI ui)`
  Sets the L&F object that renders this component.
  `void`
  `setVisible(boolean b)`
  Sets the visibility of the popup menu.
  `void`
  `show(Component invoker, int x, int y)`
  Displays the popup menu at the position x,y in the coordinate space of the component invoker.
  `void`
  `updateUI()`
  Resets the UI property to a value from the current look and feel.

  ### Methods declared in class JComponent

  `addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, unregisterKeyboardAction, update`
  Modifier and Type
  Method
  Description
  `void`
  `addAncestorListener(AncestorListener listener)`
  Registers `listener` so that it will receive `AncestorEvents` when it or any of its ancestors move or are made visible or invisible.
  `void`
  `addNotify()`
  Notifies this component that it now has a parent component.
  `void`
  `addVetoableChangeListener(VetoableChangeListener listener)`
  Adds a `VetoableChangeListener` to the listener list.
  `void`
  `computeVisibleRect(Rectangle visibleRect)`
  Returns the `Component`'s "visible rect rectangle" - the intersection of the visible rectangles for this component and all of its ancestors.
  `boolean`
  `contains(int x, int y)`
  Gives the UI delegate an opportunity to define the precise shape of this component for the sake of mouse processing.
  `JToolTip`
  `createToolTip()`
  Returns the instance of `JToolTip` that should be used to display the tooltip.
  `void`
  `disable()`
  Deprecated.
  As of JDK version 1.1, replaced by `java.awt.Component.setEnabled(boolean)`.
  `void`
  `enable()`
  Deprecated.
  As of JDK version 1.1, replaced by `java.awt.Component.setEnabled(boolean)`.
  `void`
  `firePropertyChange(String propertyName, boolean oldValue, boolean newValue)`
  Support for reporting bound property changes for boolean properties.
  `void`
  `firePropertyChange(String propertyName, int oldValue, int newValue)`
  Support for reporting bound property changes for integer properties.
  `protected void`
  `fireVetoableChange(String propertyName, Object oldValue, Object newValue)`
  Supports reporting constrained property changes.
  `ActionListener`
  `getActionForKeyStroke(KeyStroke aKeyStroke)`
  Returns the object that will perform the action registered for a given keystroke.
  `final ActionMap`
  `getActionMap()`
  Returns the `ActionMap` used to determine what `Action` to fire for particular `KeyStroke` binding.
  `float`
  `getAlignmentX()`
  Overrides `Container.getAlignmentX` to return the horizontal alignment.
  `float`
  `getAlignmentY()`
  Overrides `Container.getAlignmentY` to return the vertical alignment.
  `AncestorListener[]`
  `getAncestorListeners()`
  Returns an array of all the ancestor listeners registered on this component.
  `boolean`
  `getAutoscrolls()`
  Gets the `autoscrolls` property.
  `int`
  `getBaseline(int width, int height)`
  Returns the baseline.
  `Component.BaselineResizeBehavior`
  `getBaselineResizeBehavior()`
  Returns an enum indicating how the baseline of the component changes as the size changes.
  `Border`
  `getBorder()`
  Returns the border of this component or `null` if no border is currently set.
  `Rectangle`
  `getBounds(Rectangle rv)`
  Stores the bounds of this component into "return value" `rv` and returns `rv`.
  `final Object`
  `getClientProperty(Object key)`
  Returns the value of the property with the specified key.
  `protected Graphics`
  `getComponentGraphics(Graphics g)`
  Returns the graphics object used to paint this component.
  `JPopupMenu`
  `getComponentPopupMenu()`
  Returns `JPopupMenu` that assigned for this component.
  `int`
  `getConditionForKeyStroke(KeyStroke aKeyStroke)`
  Returns the condition that determines whether a registered action occurs in response to the specified keystroke.
  `int`
  `getDebugGraphicsOptions()`
  Returns the state of graphics debugging.
  `static Locale`
  `getDefaultLocale()`
  Returns the default locale used to initialize each JComponent's locale property upon creation.
  `FontMetrics`
  `getFontMetrics(Font font)`
  Gets the `FontMetrics` for the specified `Font`.
  `Graphics`
  `getGraphics()`
  Returns this component's graphics context, which lets you draw on a component.
  `int`
  `getHeight()`
  Returns the current height of this component.
  `boolean`
  `getInheritsPopupMenu()`
  Returns true if the JPopupMenu should be inherited from the parent.
  `final InputMap`
  `getInputMap()`
  Returns the `InputMap` that is used when the component has focus.
  `final InputMap`
  `getInputMap(int condition)`
  Returns the `InputMap` that is used during `condition`.
  `InputVerifier`
  `getInputVerifier()`
  Returns the input verifier for this component.
  `Insets`
  `getInsets()`
  If a border has been set on this component, returns the border's insets; otherwise calls `super.getInsets`.
  `Insets`
  `getInsets(Insets insets)`
  Returns an `Insets` object containing this component's inset values.
  `<T extends EventListener>
  T[]`
  `getListeners(Class<T> listenerType)`
  Returns an array of all the objects currently registered as `FooListener`s upon this `JComponent`.
  `Point`
  `getLocation(Point rv)`
  Stores the x,y origin of this component into "return value" `rv` and returns `rv`.
  `Dimension`
  `getMaximumSize()`
  If the maximum size has been set to a non-`null` value just returns it.
  `Dimension`
  `getMinimumSize()`
  If the minimum size has been set to a non-`null` value just returns it.
  `Component`
  `getNextFocusableComponent()`
  Deprecated.
  As of 1.4, replaced by `FocusTraversalPolicy`.
  `Point`
  `getPopupLocation(MouseEvent event)`
  Returns the preferred location to display the popup menu in this component's coordinate system.
  `Dimension`
  `getPreferredSize()`
  If the `preferredSize` has been set to a non-`null` value just returns it.
  `KeyStroke[]`
  `getRegisteredKeyStrokes()`
  Returns the `KeyStrokes` that will initiate registered actions.
  `JRootPane`
  `getRootPane()`
  Returns the `JRootPane` ancestor for this component.
  `Dimension`
  `getSize(Dimension rv)`
  Stores the width/height of this component into "return value" `rv` and returns `rv`.
  `Point`
  `getToolTipLocation(MouseEvent event)`
  Returns the tooltip location in this component's coordinate system.
  `String`
  `getToolTipText()`
  Returns the tooltip string that has been set with `setToolTipText`.
  `String`
  `getToolTipText(MouseEvent event)`
  Returns the string to be used as the tooltip for event.
  `Container`
  `getTopLevelAncestor()`
  Returns the top-level ancestor of this component (the containing `Window`) or `null` if this component has not been added to any container.
  `TransferHandler`
  `getTransferHandler()`
  Gets the `transferHandler` property.
  `boolean`
  `getVerifyInputWhenFocusTarget()`
  Returns the value that indicates whether the input verifier for the current focus owner will be called before this component requests focus.
  `VetoableChangeListener[]`
  `getVetoableChangeListeners()`
  Returns an array of all the vetoable change listeners registered on this component.
  `Rectangle`
  `getVisibleRect()`
  Returns the `Component`'s "visible rectangle" - the intersection of this component's visible rectangle, `new Rectangle(0, 0, getWidth(), getHeight())`, and all of its ancestors' visible rectangles.
  `int`
  `getWidth()`
  Returns the current width of this component.
  `int`
  `getX()`
  Returns the current x coordinate of the component's origin.
  `int`
  `getY()`
  Returns the current y coordinate of the component's origin.
  `void`
  `grabFocus()`
  Requests that this Component get the input focus, and that this Component's top-level ancestor become the focused Window.
  `boolean`
  `isDoubleBuffered()`
  Returns whether this component should use a buffer to paint.
  `static boolean`
  `isLightweightComponent(Component c)`
  Returns true if this component is lightweight, that is, if it doesn't have a native window system peer.
  `boolean`
  `isManagingFocus()`
  Deprecated.
  As of 1.4, replaced by `Component.setFocusTraversalKeys(int, Set)` and `Container.setFocusCycleRoot(boolean)`.
  `boolean`
  `isOpaque()`
  Returns true if this component is completely opaque.
  `boolean`
  `isOptimizedDrawingEnabled()`
  Returns true if this component tiles its children -- that is, if it can guarantee that the children will not overlap.
  `final boolean`
  `isPaintingForPrint()`
  Returns `true` if the current painting operation on this component is part of a `print` operation.
  `protected boolean`
  `isPaintingOrigin()`
  Returns `true` if a paint triggered on a child component should cause painting to originate from this Component, or one of its ancestors.
  `boolean`
  `isPaintingTile()`
  Returns true if the component is currently painting a tile.
  `boolean`
  `isRequestFocusEnabled()`
  Returns `true` if this `JComponent` should get focus; otherwise returns `false`.
  `boolean`
  `isValidateRoot()`
  If this method returns true, `revalidate` calls by descendants of this component will cause the entire tree beginning with this root to be validated.
  `void`
  `paint(Graphics g)`
  Invoked by Swing to draw components.
  `protected void`
  `paintChildren(Graphics g)`
  Paints this component's children.
  `protected void`
  `paintComponent(Graphics g)`
  Calls the UI delegate's paint method, if the UI delegate is non-`null`.
  `void`
  `paintImmediately(int x, int y, int w, int h)`
  Paints the specified region in this component and all of its descendants that overlap the region, immediately.
  `void`
  `paintImmediately(Rectangle r)`
  Paints the specified region now.
  `void`
  `print(Graphics g)`
  Invoke this method to print the component to the specified `Graphics`.
  `void`
  `printAll(Graphics g)`
  Invoke this method to print the component.
  `protected void`
  `printBorder(Graphics g)`
  Prints the component's border.
  `protected void`
  `printChildren(Graphics g)`
  Prints this component's children.
  `protected void`
  `printComponent(Graphics g)`
  This is invoked during a printing operation.
  `protected void`
  `processComponentKeyEvent(KeyEvent e)`
  Processes any key events that the component itself recognizes.
  `protected boolean`
  `processKeyBinding(KeyStroke ks, KeyEvent e, int condition, boolean pressed)`
  Invoked to process the key bindings for `ks` as the result of the `KeyEvent` `e`.
  `protected void`
  `processMouseEvent(MouseEvent e)`
  Processes mouse events occurring on this component by dispatching them to any registered `MouseListener` objects, refer to `Component.processMouseEvent(MouseEvent)` for a complete description of this method.
  `protected void`
  `processMouseMotionEvent(MouseEvent e)`
  Processes mouse motion events, such as MouseEvent.MOUSE_DRAGGED.
  `final void`
  `putClientProperty(Object key, Object value)`
  Adds an arbitrary key/value "client property" to this component.
  `void`
  `registerKeyboardAction(ActionListener anAction, String aCommand, KeyStroke aKeyStroke, int aCondition)`
  This method is now obsolete, please use a combination of `getActionMap()` and `getInputMap()` for similar behavior.
  `void`
  `registerKeyboardAction(ActionListener anAction, KeyStroke aKeyStroke, int aCondition)`
  This method is now obsolete, please use a combination of `getActionMap()` and `getInputMap()` for similar behavior.
  `void`
  `removeAncestorListener(AncestorListener listener)`
  Unregisters `listener` so that it will no longer receive `AncestorEvents`.
  `void`
  `removeNotify()`
  Notifies this component that it no longer has a parent component.
  `void`
  `removeVetoableChangeListener(VetoableChangeListener listener)`
  Removes a `VetoableChangeListener` from the listener list.
  `void`
  `repaint(long tm, int x, int y, int width, int height)`
  Adds the specified region to the dirty region list if the component is showing.
  `void`
  `repaint(Rectangle r)`
  Adds the specified region to the dirty region list if the component is showing.
  `boolean`
  `requestDefaultFocus()`
  Deprecated.
  As of 1.4, replaced by `FocusTraversalPolicy.getDefaultComponent(Container).requestFocus()`
  `void`
  `requestFocus()`
  Requests that this `Component` gets the input focus.
  `boolean`
  `requestFocus(boolean temporary)`
  Requests that this `Component` gets the input focus.
  `boolean`
  `requestFocusInWindow()`
  Requests that this `Component` gets the input focus.
  `protected boolean`
  `requestFocusInWindow(boolean temporary)`
  Requests that this `Component` gets the input focus.
  `void`
  `resetKeyboardActions()`
  Unregisters all the bindings in the first tier `InputMaps` and `ActionMap`.
  `void`
  `reshape(int x, int y, int w, int h)`
  Deprecated.
  As of JDK 5, replaced by `Component.setBounds(int, int, int, int)`.
  `void`
  `revalidate()`
  Supports deferred automatic layout.
  `void`
  `scrollRectToVisible(Rectangle aRect)`
  Forwards the `scrollRectToVisible()` message to the `JComponent`'s parent.
  `final void`
  `setActionMap(ActionMap am)`
  Sets the `ActionMap` to `am`.
  `void`
  `setAlignmentX(float alignmentX)`
  Sets the horizontal alignment.
  `void`
  `setAlignmentY(float alignmentY)`
  Sets the vertical alignment.
  `void`
  `setAutoscrolls(boolean autoscrolls)`
  Sets the `autoscrolls` property.
  `void`
  `setBackground(Color bg)`
  Sets the background color of this component.
  `void`
  `setBorder(Border border)`
  Sets the border of this component.
  `void`
  `setComponentPopupMenu(JPopupMenu popup)`
  Sets the `JPopupMenu` for this `JComponent`.
  `void`
  `setDebugGraphicsOptions(int debugOptions)`
  Enables or disables diagnostic information about every graphics operation performed within the component or one of its children.
  `static void`
  `setDefaultLocale(Locale l)`
  Sets the default locale used to initialize each JComponent's locale property upon creation.
  `void`
  `setDoubleBuffered(boolean aFlag)`
  Sets whether this component should use a buffer to paint.
  `void`
  `setEnabled(boolean enabled)`
  Sets whether or not this component is enabled.
  `void`
  `setFocusTraversalKeys(int id, Set<? extends AWTKeyStroke> keystrokes)`
  Sets the focus traversal keys for a given traversal operation for this Component.
  `void`
  `setFont(Font font)`
  Sets the font for this component.
  `void`
  `setForeground(Color fg)`
  Sets the foreground color of this component.
  `void`
  `setInheritsPopupMenu(boolean value)`
  Sets whether or not `getComponentPopupMenu` should delegate to the parent if this component does not have a `JPopupMenu` assigned to it.
  `final void`
  `setInputMap(int condition, InputMap map)`
  Sets the `InputMap` to use under the condition `condition` to `map`.
  `void`
  `setInputVerifier(InputVerifier inputVerifier)`
  Sets the input verifier for this component.
  `void`
  `setMaximumSize(Dimension maximumSize)`
  Sets the maximum size of this component to a constant value.
  `void`
  `setMinimumSize(Dimension minimumSize)`
  Sets the minimum size of this component to a constant value.
  `void`
  `setNextFocusableComponent(Component aComponent)`
  Deprecated.
  As of 1.4, replaced by `FocusTraversalPolicy`
  `void`
  `setOpaque(boolean isOpaque)`
  If true the component paints every pixel within its bounds.
  `void`
  `setPreferredSize(Dimension preferredSize)`
  Sets the preferred size of this component.
  `void`
  `setRequestFocusEnabled(boolean requestFocusEnabled)`
  Provides a hint as to whether or not this `JComponent` should get focus.
  `void`
  `setToolTipText(String text)`
  Registers the text to display in a tool tip.
  `void`
  `setTransferHandler(TransferHandler newHandler)`
  Sets the `TransferHandler`, which provides support for transfer of data into and out of this component via cut/copy/paste and drag and drop.
  `protected void`
  `setUI(ComponentUI newUI)`
  Sets the look and feel delegate for this component.
  `void`
  `setVerifyInputWhenFocusTarget(boolean verifyInputWhenFocusTarget)`
  Sets the value to indicate whether input verifier for the current focus owner will be called before this component requests focus.
  `void`
  `unregisterKeyboardAction(KeyStroke aKeyStroke)`
  This method is now obsolete.
  `void`
  `update(Graphics g)`
  Calls `paint`.

  ### Methods declared in class Container

  `add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree`
  Modifier and Type
  Method
  Description
  `Component`
  `add(Component comp)`
  Appends the specified component to the end of this container.
  `Component`
  `add(Component comp, int index)`
  Adds the specified component to this container at the given position.
  `void`
  `add(Component comp, Object constraints)`
  Adds the specified component to the end of this container.
  `void`
  `add(Component comp, Object constraints, int index)`
  Adds the specified component to this container with the specified constraints at the specified index.
  `Component`
  `add(String name, Component comp)`
  Adds the specified component to this container.
  `void`
  `addContainerListener(ContainerListener l)`
  Adds the specified container listener to receive container events from this container.
  `protected void`
  `addImpl(Component comp, Object constraints, int index)`
  Adds the specified component to this container at the specified index.
  `void`
  `addPropertyChangeListener(PropertyChangeListener listener)`
  Adds a PropertyChangeListener to the listener list.
  `void`
  `addPropertyChangeListener(String propertyName, PropertyChangeListener listener)`
  Adds a PropertyChangeListener to the listener list for a specific property.
  `void`
  `applyComponentOrientation(ComponentOrientation o)`
  Sets the `ComponentOrientation` property of this container and all components contained within it.
  `boolean`
  `areFocusTraversalKeysSet(int id)`
  Returns whether the Set of focus traversal keys for the given focus traversal operation has been explicitly defined for this Container.
  `int`
  `countComponents()`
  Deprecated.
  As of JDK version 1.1, replaced by getComponentCount().
  `void`
  `deliverEvent(Event e)`
  Deprecated.
  As of JDK version 1.1, replaced by `dispatchEvent(AWTEvent e)`
  `void`
  `doLayout()`
  Causes this container to lay out its components.
  `Component`
  `findComponentAt(int x, int y)`
  Locates the visible child component that contains the specified position.
  `Component`
  `findComponentAt(Point p)`
  Locates the visible child component that contains the specified point.
  `Component`
  `getComponent(int n)`
  Gets the nth component in this container.
  `Component`
  `getComponentAt(int x, int y)`
  Locates the component that contains the x,y position.
  `Component`
  `getComponentAt(Point p)`
  Gets the component that contains the specified point.
  `int`
  `getComponentCount()`
  Gets the number of components in this panel.
  `Component[]`
  `getComponents()`
  Gets all the components in this container.
  `int`
  `getComponentZOrder(Component comp)`
  Returns the z-order index of the component inside the container.
  `ContainerListener[]`
  `getContainerListeners()`
  Returns an array of all the container listeners registered on this container.
  `Set<AWTKeyStroke>`
  `getFocusTraversalKeys(int id)`
  Returns the Set of focus traversal keys for a given traversal operation for this Container.
  `FocusTraversalPolicy`
  `getFocusTraversalPolicy()`
  Returns the focus traversal policy that will manage keyboard traversal of this Container's children, or null if this Container is not a focus cycle root.
  `LayoutManager`
  `getLayout()`
  Gets the layout manager for this container.
  `Point`
  `getMousePosition(boolean allowChildren)`
  Returns the position of the mouse pointer in this `Container`'s coordinate space if the `Container` is under the mouse pointer, otherwise returns `null`.
  `Insets`
  `insets()`
  Deprecated.
  As of JDK version 1.1, replaced by `getInsets()`.
  `void`
  `invalidate()`
  Invalidates the container.
  `boolean`
  `isAncestorOf(Component c)`
  Checks if the component is contained in the component hierarchy of this container.
  `boolean`
  `isFocusCycleRoot()`
  Returns whether this Container is the root of a focus traversal cycle.
  `boolean`
  `isFocusCycleRoot(Container container)`
  Returns whether the specified Container is the focus cycle root of this Container's focus traversal cycle.
  `final boolean`
  `isFocusTraversalPolicyProvider()`
  Returns whether this container provides focus traversal policy.
  `boolean`
  `isFocusTraversalPolicySet()`
  Returns whether the focus traversal policy has been explicitly set for this Container.
  `void`
  `layout()`
  Deprecated.
  As of JDK version 1.1, replaced by `doLayout()`.
  `void`
  `list(PrintStream out, int indent)`
  Prints a listing of this container to the specified output stream.
  `void`
  `list(PrintWriter out, int indent)`
  Prints out a list, starting at the specified indentation, to the specified print writer.
  `Component`
  `locate(int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by `getComponentAt(int, int)`.
  `Dimension`
  `minimumSize()`
  Deprecated.
  As of JDK version 1.1, replaced by `getMinimumSize()`.
  `void`
  `paintComponents(Graphics g)`
  Paints each of the components in this container.
  `Dimension`
  `preferredSize()`
  Deprecated.
  As of JDK version 1.1, replaced by `getPreferredSize()`.
  `void`
  `printComponents(Graphics g)`
  Prints each of the components in this container.
  `protected void`
  `processContainerEvent(ContainerEvent e)`
  Processes container events occurring on this container by dispatching them to any registered ContainerListener objects.
  `protected void`
  `processEvent(AWTEvent e)`
  Processes events on this container.
  `void`
  `remove(Component comp)`
  Removes the specified component from this container.
  `void`
  `removeAll()`
  Removes all the components from this container.
  `void`
  `removeContainerListener(ContainerListener l)`
  Removes the specified container listener so it no longer receives container events from this container.
  `void`
  `setComponentZOrder(Component comp, int index)`
  Moves the specified component to the specified z-order index in the container.
  `void`
  `setFocusCycleRoot(boolean focusCycleRoot)`
  Sets whether this Container is the root of a focus traversal cycle.
  `void`
  `setFocusTraversalPolicy(FocusTraversalPolicy policy)`
  Sets the focus traversal policy that will manage keyboard traversal of this Container's children, if this Container is a focus cycle root.
  `final void`
  `setFocusTraversalPolicyProvider(boolean provider)`
  Sets whether this container will be used to provide focus traversal policy.
  `void`
  `setLayout(LayoutManager mgr)`
  Sets the layout manager for this container.
  `void`
  `transferFocusDownCycle()`
  Transfers the focus down one focus traversal cycle.
  `void`
  `validate()`
  Validates this container and all of its subcomponents.
  `protected void`
  `validateTree()`
  Recursively descends the container tree and recomputes the layout for any subtrees marked as needing it (those marked as invalid).

  ### Methods declared in class Component

  `action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setMixingCutoutShape, setName, setSize, setSize, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle`
  Modifier and Type
  Method
  Description
  `boolean`
  `action(Event evt, Object what)`
  Deprecated.
  As of JDK version 1.1, should register this component as ActionListener on component which fires action events.
  `void`
  `add(PopupMenu popup)`
  Adds the specified popup menu to the component.
  `void`
  `addComponentListener(ComponentListener l)`
  Adds the specified component listener to receive component events from this component.
  `void`
  `addFocusListener(FocusListener l)`
  Adds the specified focus listener to receive focus events from this component when this component gains input focus.
  `void`
  `addHierarchyBoundsListener(HierarchyBoundsListener l)`
  Adds the specified hierarchy bounds listener to receive hierarchy bounds events from this component when the hierarchy to which this container belongs changes.
  `void`
  `addHierarchyListener(HierarchyListener l)`
  Adds the specified hierarchy listener to receive hierarchy changed events from this component when the hierarchy to which this container belongs changes.
  `void`
  `addInputMethodListener(InputMethodListener l)`
  Adds the specified input method listener to receive input method events from this component.
  `void`
  `addKeyListener(KeyListener l)`
  Adds the specified key listener to receive key events from this component.
  `void`
  `addMouseListener(MouseListener l)`
  Adds the specified mouse listener to receive mouse events from this component.
  `void`
  `addMouseMotionListener(MouseMotionListener l)`
  Adds the specified mouse motion listener to receive mouse motion events from this component.
  `void`
  `addMouseWheelListener(MouseWheelListener l)`
  Adds the specified mouse wheel listener to receive mouse wheel events from this component.
  `Rectangle`
  `bounds()`
  Deprecated.
  As of JDK version 1.1, replaced by `getBounds()`.
  `int`
  `checkImage(Image image, int width, int height, ImageObserver observer)`
  Returns the status of the construction of a screen representation of the specified image.
  `int`
  `checkImage(Image image, ImageObserver observer)`
  Returns the status of the construction of a screen representation of the specified image.
  `protected AWTEvent`
  `coalesceEvents(AWTEvent existingEvent, AWTEvent newEvent)`
  Potentially coalesce an event being posted with an existing event.
  `boolean`
  `contains(Point p)`
  Checks whether this component "contains" the specified point, where the point's x and y coordinates are defined to be relative to the coordinate system of this component.
  `Image`
  `createImage(int width, int height)`
  Creates an off-screen drawable image to be used for double buffering.
  `Image`
  `createImage(ImageProducer producer)`
  Creates an image from the specified image producer.
  `VolatileImage`
  `createVolatileImage(int width, int height)`
  Creates a volatile off-screen drawable image to be used for double buffering.
  `VolatileImage`
  `createVolatileImage(int width, int height, ImageCapabilities caps)`
  Creates a volatile off-screen drawable image, with the given capabilities.
  `protected final void`
  `disableEvents(long eventsToDisable)`
  Disables the events defined by the specified event mask parameter from being delivered to this component.
  `final void`
  `dispatchEvent(AWTEvent e)`
  Dispatches an event to this component or one of its sub components.
  `void`
  `enable(boolean b)`
  Deprecated.
  As of JDK version 1.1, replaced by `setEnabled(boolean)`.
  `protected final void`
  `enableEvents(long eventsToEnable)`
  Enables the events defined by the specified event mask parameter to be delivered to this component.
  `void`
  `enableInputMethods(boolean enable)`
  Enables or disables input method support for this component.
  `void`
  `firePropertyChange(String propertyName, byte oldValue, byte newValue)`
  Reports a bound property change.
  `void`
  `firePropertyChange(String propertyName, char oldValue, char newValue)`
  Reports a bound property change.
  `void`
  `firePropertyChange(String propertyName, double oldValue, double newValue)`
  Reports a bound property change.
  `void`
  `firePropertyChange(String propertyName, float oldValue, float newValue)`
  Reports a bound property change.
  `void`
  `firePropertyChange(String propertyName, long oldValue, long newValue)`
  Reports a bound property change.
  `void`
  `firePropertyChange(String propertyName, short oldValue, short newValue)`
  Reports a bound property change.
  `protected void`
  `firePropertyChange(String propertyName, Object oldValue, Object newValue)`
  Support for reporting bound property changes for Object properties.
  `Color`
  `getBackground()`
  Gets the background color of this component.
  `Rectangle`
  `getBounds()`
  Gets the bounds of this component in the form of a `Rectangle` object.
  `ColorModel`
  `getColorModel()`
  Gets the instance of `ColorModel` used to display the component on the output device.
  `ComponentListener[]`
  `getComponentListeners()`
  Returns an array of all the component listeners registered on this component.
  `ComponentOrientation`
  `getComponentOrientation()`
  Retrieves the language-sensitive orientation that is to be used to order the elements or text within this component.
  `Cursor`
  `getCursor()`
  Gets the cursor set in the component.
  `DropTarget`
  `getDropTarget()`
  Gets the `DropTarget` associated with this `Component`.
  `Container`
  `getFocusCycleRootAncestor()`
  Returns the Container which is the focus cycle root of this Component's focus traversal cycle.
  `FocusListener[]`
  `getFocusListeners()`
  Returns an array of all the focus listeners registered on this component.
  `boolean`
  `getFocusTraversalKeysEnabled()`
  Returns whether focus traversal keys are enabled for this Component.
  `Font`
  `getFont()`
  Gets the font of this component.
  `Color`
  `getForeground()`
  Gets the foreground color of this component.
  `GraphicsConfiguration`
  `getGraphicsConfiguration()`
  Gets the `GraphicsConfiguration` associated with this `Component`.
  `HierarchyBoundsListener[]`
  `getHierarchyBoundsListeners()`
  Returns an array of all the hierarchy bounds listeners registered on this component.
  `HierarchyListener[]`
  `getHierarchyListeners()`
  Returns an array of all the hierarchy listeners registered on this component.
  `boolean`
  `getIgnoreRepaint()`
  Returns whether or not paint messages received from the operating system should be ignored.
  `InputContext`
  `getInputContext()`
  Gets the input context used by this component for handling the communication with input methods when text is entered in this component.
  `InputMethodListener[]`
  `getInputMethodListeners()`
  Returns an array of all the input method listeners registered on this component.
  `InputMethodRequests`
  `getInputMethodRequests()`
  Gets the input method request handler which supports requests from input methods for this component.
  `KeyListener[]`
  `getKeyListeners()`
  Returns an array of all the key listeners registered on this component.
  `Locale`
  `getLocale()`
  Gets the locale of this component.
  `Point`
  `getLocation()`
  Gets the location of this component in the form of a point specifying the component's top-left corner.
  `Point`
  `getLocationOnScreen()`
  Gets the location of this component in the form of a point specifying the component's top-left corner in the screen's coordinate space.
  `MouseListener[]`
  `getMouseListeners()`
  Returns an array of all the mouse listeners registered on this component.
  `MouseMotionListener[]`
  `getMouseMotionListeners()`
  Returns an array of all the mouse motion listeners registered on this component.
  `Point`
  `getMousePosition()`
  Returns the position of the mouse pointer in this `Component`'s coordinate space if the `Component` is directly under the mouse pointer, otherwise returns `null`.
  `MouseWheelListener[]`
  `getMouseWheelListeners()`
  Returns an array of all the mouse wheel listeners registered on this component.
  `String`
  `getName()`
  Gets the name of the component.
  `Container`
  `getParent()`
  Gets the parent of this component.
  `PropertyChangeListener[]`
  `getPropertyChangeListeners()`
  Returns an array of all the property change listeners registered on this component.
  `PropertyChangeListener[]`
  `getPropertyChangeListeners(String propertyName)`
  Returns an array of all the listeners which have been associated with the named property.
  `Dimension`
  `getSize()`
  Returns the size of this component in the form of a `Dimension` object.
  `Toolkit`
  `getToolkit()`
  Gets the toolkit of this component.
  `final Object`
  `getTreeLock()`
  Gets this component's locking object (the object that owns the thread synchronization monitor) for AWT component-tree and layout operations.
  `boolean`
  `gotFocus(Event evt, Object what)`
  Deprecated.
  As of JDK version 1.1, replaced by processFocusEvent(FocusEvent).
  `boolean`
  `handleEvent(Event evt)`
  Deprecated.
  As of JDK version 1.1 replaced by processEvent(AWTEvent).
  `boolean`
  `hasFocus()`
  Returns `true` if this `Component` is the focus owner.
  `boolean`
  `imageUpdate(Image img, int infoflags, int x, int y, int w, int h)`
  Repaints the component when the image has changed.
  `boolean`
  `inside(int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by contains(int, int).
  `boolean`
  `isBackgroundSet()`
  Returns whether the background color has been explicitly set for this Component.
  `boolean`
  `isCursorSet()`
  Returns whether the cursor has been explicitly set for this Component.
  `boolean`
  `isDisplayable()`
  Determines whether this component is displayable.
  `boolean`
  `isEnabled()`
  Determines whether this component is enabled.
  `boolean`
  `isFocusable()`
  Returns whether this Component can be focused.
  `boolean`
  `isFocusOwner()`
  Returns `true` if this `Component` is the focus owner.
  `boolean`
  `isFontSet()`
  Returns whether the font has been explicitly set for this Component.
  `boolean`
  `isForegroundSet()`
  Returns whether the foreground color has been explicitly set for this Component.
  `boolean`
  `isLightweight()`
  A lightweight component doesn't have a native toolkit peer.
  `boolean`
  `isMaximumSizeSet()`
  Returns true if the maximum size has been set to a non-`null` value otherwise returns false.
  `boolean`
  `isMinimumSizeSet()`
  Returns whether or not `setMinimumSize` has been invoked with a non-null value.
  `boolean`
  `isPreferredSizeSet()`
  Returns true if the preferred size has been set to a non-`null` value otherwise returns false.
  `boolean`
  `isShowing()`
  Determines whether this component is showing on screen.
  `boolean`
  `isValid()`
  Determines whether this component is valid.
  `boolean`
  `keyDown(Event evt, int key)`
  Deprecated.
  As of JDK version 1.1, replaced by processKeyEvent(KeyEvent).
  `boolean`
  `keyUp(Event evt, int key)`
  Deprecated.
  As of JDK version 1.1, replaced by processKeyEvent(KeyEvent).
  `void`
  `list()`
  Prints a listing of this component to the standard system output stream `System.out`.
  `void`
  `list(PrintStream out)`
  Prints a listing of this component to the specified output stream.
  `void`
  `list(PrintWriter out)`
  Prints a listing to the specified print writer.
  `Point`
  `location()`
  Deprecated.
  As of JDK version 1.1, replaced by `getLocation()`.
  `boolean`
  `lostFocus(Event evt, Object what)`
  Deprecated.
  As of JDK version 1.1, replaced by processFocusEvent(FocusEvent).
  `boolean`
  `mouseDown(Event evt, int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
  `boolean`
  `mouseDrag(Event evt, int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by processMouseMotionEvent(MouseEvent).
  `boolean`
  `mouseEnter(Event evt, int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
  `boolean`
  `mouseExit(Event evt, int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
  `boolean`
  `mouseMove(Event evt, int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by processMouseMotionEvent(MouseEvent).
  `boolean`
  `mouseUp(Event evt, int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
  `void`
  `move(int x, int y)`
  Deprecated.
  As of JDK version 1.1, replaced by `setLocation(int, int)`.
  `void`
  `nextFocus()`
  Deprecated.
  As of JDK version 1.1, replaced by transferFocus().
  `void`
  `paintAll(Graphics g)`
  Paints this component and all of its subcomponents.
  `boolean`
  `postEvent(Event e)`
  Deprecated.
  As of JDK version 1.1, replaced by dispatchEvent(AWTEvent).
  `boolean`
  `prepareImage(Image image, int width, int height, ImageObserver observer)`
  Prepares an image for rendering on this component at the specified width and height.
  `boolean`
  `prepareImage(Image image, ImageObserver observer)`
  Prepares an image for rendering on this component.
  `protected void`
  `processComponentEvent(ComponentEvent e)`
  Processes component events occurring on this component by dispatching them to any registered `ComponentListener` objects.
  `protected void`
  `processFocusEvent(FocusEvent e)`
  Processes focus events occurring on this component by dispatching them to any registered `FocusListener` objects.
  `protected void`
  `processHierarchyBoundsEvent(HierarchyEvent e)`
  Processes hierarchy bounds events occurring on this component by dispatching them to any registered `HierarchyBoundsListener` objects.
  `protected void`
  `processHierarchyEvent(HierarchyEvent e)`
  Processes hierarchy events occurring on this component by dispatching them to any registered `HierarchyListener` objects.
  `protected void`
  `processInputMethodEvent(InputMethodEvent e)`
  Processes input method events occurring on this component by dispatching them to any registered `InputMethodListener` objects.
  `protected void`
  `processMouseWheelEvent(MouseWheelEvent e)`
  Processes mouse wheel events occurring on this component by dispatching them to any registered `MouseWheelListener` objects.
  `void`
  `remove(MenuComponent popup)`
  Removes the specified popup menu from the component.
  `void`
  `removeComponentListener(ComponentListener l)`
  Removes the specified component listener so that it no longer receives component events from this component.
  `void`
  `removeFocusListener(FocusListener l)`
  Removes the specified focus listener so that it no longer receives focus events from this component.
  `void`
  `removeHierarchyBoundsListener(HierarchyBoundsListener l)`
  Removes the specified hierarchy bounds listener so that it no longer receives hierarchy bounds events from this component.
  `void`
  `removeHierarchyListener(HierarchyListener l)`
  Removes the specified hierarchy listener so that it no longer receives hierarchy changed events from this component.
  `void`
  `removeInputMethodListener(InputMethodListener l)`
  Removes the specified input method listener so that it no longer receives input method events from this component.
  `void`
  `removeKeyListener(KeyListener l)`
  Removes the specified key listener so that it no longer receives key events from this component.
  `void`
  `removeMouseListener(MouseListener l)`
  Removes the specified mouse listener so that it no longer receives mouse events from this component.
  `void`
  `removeMouseMotionListener(MouseMotionListener l)`
  Removes the specified mouse motion listener so that it no longer receives mouse motion events from this component.
  `void`
  `removeMouseWheelListener(MouseWheelListener l)`
  Removes the specified mouse wheel listener so that it no longer receives mouse wheel events from this component.
  `void`
  `removePropertyChangeListener(PropertyChangeListener listener)`
  Removes a PropertyChangeListener from the listener list.
  `void`
  `removePropertyChangeListener(String propertyName, PropertyChangeListener listener)`
  Removes a `PropertyChangeListener` from the listener list for a specific property.
  `void`
  `repaint()`
  Repaints this component.
  `void`
  `repaint(int x, int y, int width, int height)`
  Repaints the specified rectangle of this component.
  `void`
  `repaint(long tm)`
  Repaints the component.
  `protected boolean`
  `requestFocus(boolean temporary, FocusEvent.Cause cause)`
  Requests by the reason of `cause` that this `Component` get the input focus, and that this `Component`'s top-level ancestor become the focused `Window`.
  `void`
  `requestFocus(FocusEvent.Cause cause)`
  Requests by the reason of `cause` that this Component get the input focus, and that this Component's top-level ancestor become the focused Window.
  `boolean`
  `requestFocusInWindow(FocusEvent.Cause cause)`
  Requests by the reason of `cause` that this Component get the input focus, if this Component's top-level ancestor is already the focused Window.
  `void`
  `resize(int width, int height)`
  Deprecated.
  As of JDK version 1.1, replaced by `setSize(int, int)`.
  `void`
  `resize(Dimension d)`
  Deprecated.
  As of JDK version 1.1, replaced by `setSize(Dimension)`.
  `void`
  `setBounds(int x, int y, int width, int height)`
  Moves and resizes this component.
  `void`
  `setBounds(Rectangle r)`
  Moves and resizes this component to conform to the new bounding rectangle `r`.
  `void`
  `setComponentOrientation(ComponentOrientation o)`
  Sets the language-sensitive orientation that is to be used to order the elements or text within this component.
  `void`
  `setCursor(Cursor cursor)`
  Sets the cursor image to the specified cursor.
  `void`
  `setDropTarget(DropTarget dt)`
  Associate a `DropTarget` with this component.
  `void`
  `setFocusable(boolean focusable)`
  Sets the focusable state of this Component to the specified value.
  `void`
  `setFocusTraversalKeysEnabled(boolean focusTraversalKeysEnabled)`
  Sets whether focus traversal keys are enabled for this Component.
  `void`
  `setIgnoreRepaint(boolean ignoreRepaint)`
  Sets whether or not paint messages received from the operating system should be ignored.
  `void`
  `setLocale(Locale l)`
  Sets the locale of this component.
  `void`
  `setLocation(Point p)`
  Moves this component to a new location.
  `void`
  `setMixingCutoutShape(Shape shape)`
  Sets a 'mixing-cutout' shape for this lightweight component.
  `void`
  `setName(String name)`
  Sets the name of the component to the specified string.
  `void`
  `setSize(int width, int height)`
  Resizes this component so that it has width `width` and height `height`.
  `void`
  `setSize(Dimension d)`
  Resizes this component so that it has width `d.width` and height `d.height`.
  `void`
  `show(boolean b)`
  Deprecated.
  As of JDK version 1.1, replaced by `setVisible(boolean)`.
  `Dimension`
  `size()`
  Deprecated.
  As of JDK version 1.1, replaced by `getSize()`.
  `String`
  `toString()`
  Returns a string representation of this component and its values.
  `void`
  `transferFocus()`
  Transfers the focus to the next component, as though this Component were the focus owner.
  `void`
  `transferFocusBackward()`
  Transfers the focus to the previous component, as though this Component were the focus owner.
  `void`
  `transferFocusUpCycle()`
  Transfers the focus up one focus traversal cycle.

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`
  Modifier and Type
  Method
  Description
  `protected Object`
  `clone()`
  Creates and returns a copy of this object.
  `boolean`
  `equals(Object obj)`
  Indicates whether some other object is "equal to" this one.
  `protected void`
  `finalize()`
  Deprecated, for removal: This API element is subject to removal in a future version.
  Finalization is deprecated and subject to removal in a future release.
  `final Class<?>`
  `getClass()`
  Returns the runtime class of this `Object`.
  `int`
  `hashCode()`
  Returns a hash code value for this object.
  `final void`
  `notify()`
  Wakes up a single thread that is waiting on this object's monitor.
  `final void`
  `notifyAll()`
  Wakes up all threads that are waiting on this object's monitor.
  `final void`
  `wait()`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
  `final void`
  `wait(long timeoutMillis)`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
  `final void`
  `wait(long timeoutMillis, int nanos)`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  ### Methods declared in interface ComboPopup

  `isVisible`
  Modifier and Type
  Method
  Description
  `boolean`
  `isVisible()`
  Returns true if the popup is visible (currently being displayed).

- ## Field Details

  - ### comboBox

    protected JComboBox<Object> comboBox
    The instance of `JComboBox`.

  - ### list

    protected JList<Object> list
    This protected field is implementation specific. Do not access directly or override. Use the accessor methods instead.
    See Also:
      - `getList()`
      - `createList()`

  - ### scroller

    protected JScrollPane scroller
    This protected field is implementation specific. Do not access directly or override. Use the create method instead
    See Also:
      - `createScroller()`

  - ### valueIsAdjusting

    protected boolean valueIsAdjusting
    As of Java 2 platform v1.4 this previously undocumented field is no longer used.

  - ### mouseMotionListener

    protected MouseMotionListener mouseMotionListener
    This protected field is implementation specific. Do not access directly or override. Use the accessor or create methods instead.
    See Also:
      - `getMouseMotionListener()`
      - `createMouseMotionListener()`

  - ### mouseListener

    protected MouseListener mouseListener
    This protected field is implementation specific. Do not access directly or override. Use the accessor or create methods instead.
    See Also:
      - `getMouseListener()`
      - `createMouseListener()`

  - ### keyListener

    protected KeyListener keyListener
    This protected field is implementation specific. Do not access directly or override. Use the accessor or create methods instead.
    See Also:
      - `getKeyListener()`
      - `createKeyListener()`

  - ### listSelectionListener

    protected ListSelectionListener listSelectionListener
    This protected field is implementation specific. Do not access directly or override. Use the create method instead.
    See Also:
      - `createListSelectionListener()`

  - ### listMouseListener

    protected MouseListener listMouseListener
    This protected field is implementation specific. Do not access directly or override. Use the create method instead.
    See Also:
      - `createListMouseListener()`

  - ### listMouseMotionListener

    protected MouseMotionListener listMouseMotionListener
    This protected field is implementation specific. Do not access directly or override. Use the create method instead
    See Also:
      - `createListMouseMotionListener()`

  - ### propertyChangeListener

    protected PropertyChangeListener propertyChangeListener
    This protected field is implementation specific. Do not access directly or override. Use the create method instead
    See Also:
      - `createPropertyChangeListener()`

  - ### listDataListener

    protected ListDataListener listDataListener
    This protected field is implementation specific. Do not access directly or override. Use the create method instead
    See Also:
      - `createListDataListener()`

  - ### itemListener

    protected ItemListener itemListener
    This protected field is implementation specific. Do not access directly or override. Use the create method instead
    See Also:
      - `createItemListener()`

  - ### autoscrollTimer

    protected Timer autoscrollTimer
    This protected field is implementation specific. Do not access directly or override.

  - ### hasEntered

    protected boolean hasEntered
    `true` if the mouse cursor is in the popup.

  - ### isAutoScrolling

    protected boolean isAutoScrolling
    If `true` the auto-scrolling is enabled.

  - ### scrollDirection

    protected int scrollDirection
    The direction of scrolling.

  - ### SCROLL_UP

    protected static final int SCROLL_UP
    The direction of scrolling up.
    See Also:
      - Constant Field Values

  - ### SCROLL_DOWN

    protected static final int SCROLL_DOWN
    The direction of scrolling down.
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### BasicComboPopup

    public BasicComboPopup(JComboBox<Object> combo)
    Constructs a new instance of `BasicComboPopup`.
    Parameters:
      `combo` - an instance of `JComboBox`

- ## Method Details

  - ### show

    public void show()
    Implementation of ComboPopup.show().
    Specified by:
      `show` in interface `ComboPopup`
    Overrides:
      `show` in class `Component`

  - ### hide

    public void hide()
    Implementation of ComboPopup.hide().
    Specified by:
      `hide` in interface `ComboPopup`
    Overrides:
      `hide` in class `JComponent`

  - ### getList

    public JList<Object> getList()
    Implementation of ComboPopup.getList().
    Specified by:
      `getList` in interface `ComboPopup`
    Returns:
      the list that is being used to draw the items in the combo box

  - ### getMouseListener

    public MouseListener getMouseListener()
    Implementation of ComboPopup.getMouseListener().
    Specified by:
      `getMouseListener` in interface `ComboPopup`
    Returns:
      a `MouseListener` or null
    See Also:
      - `ComboPopup.getMouseListener()`

  - ### getMouseMotionListener

    public MouseMotionListener getMouseMotionListener()
    Implementation of ComboPopup.getMouseMotionListener().
    Specified by:
      `getMouseMotionListener` in interface `ComboPopup`
    Returns:
      a `MouseMotionListener` or null
    See Also:
      - `ComboPopup.getMouseMotionListener()`

  - ### getKeyListener

    public KeyListener getKeyListener()
    Implementation of ComboPopup.getKeyListener().
    Specified by:
      `getKeyListener` in interface `ComboPopup`
    Returns:
      a `KeyListener` or null
    See Also:
      - `ComboPopup.getKeyListener()`

  - ### uninstallingUI

    public void uninstallingUI()
    Called when the UI is uninstalling. Since this popup isn't in the component tree, it won't get it's uninstallUI() called. It removes the listeners that were added in addComboBoxListeners().
    Specified by:
      `uninstallingUI` in interface `ComboPopup`

  - ### uninstallComboBoxModelListeners

    protected void uninstallComboBoxModelListeners(ComboBoxModel<?> model)
    Removes the listeners from the combo box model
    Parameters:
      `model` - The combo box model to install listeners
    See Also:
      - `installComboBoxModelListeners(ComboBoxModel)`

  - ### uninstallKeyboardActions

    protected void uninstallKeyboardActions()
    Unregisters keyboard actions.

  - ### createMouseListener

    protected MouseListener createMouseListener()
    Creates a listener that will watch for mouse-press and release events on the combo box. Warning: When overriding this method, make sure to maintain the existing behavior.
    Returns:
      a `MouseListener` which will be added to the combo box or null

  - ### createMouseMotionListener

    protected MouseMotionListener createMouseMotionListener()
    Creates the mouse motion listener which will be added to the combo box. Warning: When overriding this method, make sure to maintain the existing behavior.
    Returns:
      a `MouseMotionListener` which will be added to the combo box or null

  - ### createKeyListener

    protected KeyListener createKeyListener()
    Creates the key listener that will be added to the combo box. If this method returns null then it will not be added to the combo box.
    Returns:
      a `KeyListener` or null

  - ### createListSelectionListener

    protected ListSelectionListener createListSelectionListener()
    Creates a list selection listener that watches for selection changes in the popup's list. If this method returns null then it will not be added to the popup list.
    Returns:
      an instance of a `ListSelectionListener` or null

  - ### createListDataListener

    protected ListDataListener createListDataListener()
    Creates a list data listener which will be added to the `ComboBoxModel`. If this method returns null then it will not be added to the combo box model.
    Returns:
      an instance of a `ListDataListener` or null

  - ### createListMouseListener

    protected MouseListener createListMouseListener()
    Creates a mouse listener that watches for mouse events in the popup's list. If this method returns null then it will not be added to the combo box.
    Returns:
      an instance of a `MouseListener` or null

  - ### createListMouseMotionListener

    protected MouseMotionListener createListMouseMotionListener()
    Creates a mouse motion listener that watches for mouse motion events in the popup's list. If this method returns null then it will not be added to the combo box.
    Returns:
      an instance of a `MouseMotionListener` or null

  - ### createPropertyChangeListener

    protected PropertyChangeListener createPropertyChangeListener()
    Creates a `PropertyChangeListener` which will be added to the combo box. If this method returns null then it will not be added to the combo box.
    Returns:
      an instance of a `PropertyChangeListener` or null

  - ### createItemListener

    protected ItemListener createItemListener()
    Creates an `ItemListener` which will be added to the combo box. If this method returns null then it will not be added to the combo box.

    Subclasses may override this method to return instances of their own ItemEvent handlers.

    Returns:
      an instance of an `ItemListener` or null

  - ### createList

    protected JList<Object> createList()
    Creates the JList used in the popup to display the items in the combo box model. This method is called when the UI class is created.
    Returns:
      a `JList` used to display the combo box items

  - ### configureList

    protected void configureList()
    Configures the list which is used to hold the combo box items in the popup. This method is called when the UI class is created.
    See Also:
      - `createList()`

  - ### installListListeners

    protected void installListListeners()
    Adds the listeners to the list control.

  - ### createScroller

    protected JScrollPane createScroller()
    Creates the scroll pane which houses the scrollable list.
    Returns:
      the scroll pane which houses the scrollable list

  - ### configureScroller

    protected void configureScroller()
    Configures the scrollable portion which holds the list within the combo box popup. This method is called when the UI class is created.

  - ### configurePopup

    protected void configurePopup()
    Configures the popup portion of the combo box. This method is called when the UI class is created.

  - ### installComboBoxListeners

    protected void installComboBoxListeners()
    This method adds the necessary listeners to the JComboBox.

  - ### installComboBoxModelListeners

    protected void installComboBoxModelListeners(ComboBoxModel<?> model)
    Installs the listeners on the combo box model. Any listeners installed on the combo box model should be removed in `uninstallComboBoxModelListeners`.
    Parameters:
      `model` - The combo box model to install listeners
    See Also:
      - `uninstallComboBoxModelListeners(ComboBoxModel)`

  - ### installKeyboardActions

    protected void installKeyboardActions()
    Registers keyboard actions.

  - ### isFocusTraversable

    public boolean isFocusTraversable()
    Overridden to unconditionally return false.
    Overrides:
      `isFocusTraversable` in class `Component`
    Returns:
      `true` if this `Component` is focusable; `false` otherwise
    See Also:
      - `Component.setFocusable(boolean)`

  - ### startAutoScrolling

    protected void startAutoScrolling(int direction)
    This protected method is implementation specific and should be private. do not call or override.
    Parameters:
      `direction` - the direction of scrolling

  - ### stopAutoScrolling

    protected void stopAutoScrolling()
    This protected method is implementation specific and should be private. do not call or override.

  - ### autoScrollUp

    protected void autoScrollUp()
    This protected method is implementation specific and should be private. do not call or override.

  - ### autoScrollDown

    protected void autoScrollDown()
    This protected method is implementation specific and should be private. do not call or override.

  - ### getAccessibleContext

    public AccessibleContext getAccessibleContext()
    Gets the AccessibleContext associated with this BasicComboPopup. The AccessibleContext will have its parent set to the ComboBox.
    Specified by:
      `getAccessibleContext` in interface `Accessible`
    Overrides:
      `getAccessibleContext` in class `JPopupMenu`
    Returns:
      an AccessibleContext for the BasicComboPopup
    Since:
      1.5

  - ### delegateFocus

    protected void delegateFocus(MouseEvent e)
    This is a utility method that helps event handlers figure out where to send the focus when the popup is brought up. The standard implementation delegates the focus to the editor (if the combo box is editable) or to the JComboBox if it is not editable.
    Parameters:
      `e` - a mouse event

  - ### togglePopup

    protected void togglePopup()
    Makes the popup visible if it is hidden and makes it hidden if it is visible.

  - ### convertMouseEvent

    protected MouseEvent convertMouseEvent(MouseEvent e)
    Converts mouse event.
    Parameters:
      `e` - a mouse event
    Returns:
      converted mouse event

  - ### getPopupHeightForRowCount

    protected int getPopupHeightForRowCount(int maxRowCount)
    Retrieves the height of the popup based on the current ListCellRenderer and the maximum row count.
    Parameters:
      `maxRowCount` - the row count
    Returns:
      the height of the popup

  - ### computePopupBounds

    protected Rectangle computePopupBounds(int px, int py, int pw, int ph)
    Calculate the placement and size of the popup portion of the combo box based on the combo box location and the enclosing screen bounds. If no transformations are required, then the returned rectangle will have the same values as the parameters.
    Parameters:
      `px` - starting x location
      `py` - starting y location
      `pw` - starting width
      `ph` - starting height
    Returns:
      a rectangle which represents the placement and size of the popup

  - ### updateListBoxSelectionForEvent

    protected void updateListBoxSelectionForEvent(MouseEvent anEvent, boolean shouldScroll)
    A utility method used by the event listeners. Given a mouse event, it changes the list selection to the list item below the mouse.
    Parameters:
      `anEvent` - a mouse event
      `shouldScroll` - if `true` list should be scrolled.