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/OpenJDK 21

Class JMenu

java.lang.Object
java.awt.Component
java.awt.Container
javax.swing.JComponent
javax.swing.AbstractButton
javax.swing.JMenuItem
javax.swing.JMenu
All Implemented Interfaces:
ImageObserver, ItemSelectable, MenuContainer, Serializable, Accessible, MenuElement, SwingConstants 
@JavaBean(description="A popup window containing menu items displayed in a menu bar.") public class JMenu extends JMenuItem implements Accessible, MenuElement
An implementation of a menu -- a popup window containing JMenuItems that is displayed when the user selects an item on the JMenuBar. In addition to JMenuItems, a JMenu can also contain JSeparators.

In essence, a menu is a button with an associated JPopupMenu. When the "button" is pressed, the JPopupMenu appears. If the "button" is on the JMenuBar, the menu is a top-level window. If the "button" is another menu item, then the JPopupMenu is "pull-right" menu.

Menus can be configured, and to some degree controlled, by Actions. Using an Action with a menu has many benefits beyond directly configuring a menu. Refer to Swing Components Supporting Action for more details, and you can find more information in How to Use Actions, a section in The Java Tutorial.

For information and examples of using menus see How to Use Menus, a section in The Java Tutorial.

Warning: Swing is not thread safe. For more information see Swing's Threading Policy.

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.

Since:
1.2
See Also:

Nested Class Summary

Modifier and Type Class Description
protected class  JMenu.AccessibleJMenu
This class implements accessibility support for the JMenu class.
protected class  JMenu.WinListener
A listener class that watches for a popup window closing.

Nested classes/interfaces declared in class javax.swing.JMenuItem

JMenuItem.AccessibleJMenuItem

Nested classes/interfaces declared in class javax.swing.AbstractButton

AbstractButton.AccessibleAbstractButton, AbstractButton.ButtonChangeListener

Nested classes/interfaces declared in class javax.swing.JComponent

JComponent.AccessibleJComponent

Nested classes/interfaces declared in class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces declared in class java.awt.Component

Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Modifier and Type Field Description
protected JMenu.WinListener popupListener
The window-closing listener for the popup.

Fields declared in class javax.swing.AbstractButton

actionListener, BORDER_PAINTED_CHANGED_PROPERTY, changeEvent, changeListener, CONTENT_AREA_FILLED_CHANGED_PROPERTY, DISABLED_ICON_CHANGED_PROPERTY, DISABLED_SELECTED_ICON_CHANGED_PROPERTY, FOCUS_PAINTED_CHANGED_PROPERTY, HORIZONTAL_ALIGNMENT_CHANGED_PROPERTY, HORIZONTAL_TEXT_POSITION_CHANGED_PROPERTY, ICON_CHANGED_PROPERTY, itemListener, MARGIN_CHANGED_PROPERTY, MNEMONIC_CHANGED_PROPERTY, model, MODEL_CHANGED_PROPERTY, PRESSED_ICON_CHANGED_PROPERTY, ROLLOVER_ENABLED_CHANGED_PROPERTY, ROLLOVER_ICON_CHANGED_PROPERTY, ROLLOVER_SELECTED_ICON_CHANGED_PROPERTY, SELECTED_ICON_CHANGED_PROPERTY, TEXT_CHANGED_PROPERTY, VERTICAL_ALIGNMENT_CHANGED_PROPERTY, VERTICAL_TEXT_POSITION_CHANGED_PROPERTY

Fields declared in class javax.swing.JComponent

listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW

Fields declared in class java.awt.Component

accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields declared in interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Fields declared in interface javax.swing.SwingConstants

BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST

Constructor Summary

Constructor Description
JMenu()
Constructs a new JMenu with no text.
JMenu(String s)
Constructs a new JMenu with the supplied string as its text.
JMenu(String s, boolean b)
Constructs a new JMenu with the supplied string as its text and specified as a tear-off menu or not.
JMenu(Action a)
Constructs a menu whose properties are taken from the Action supplied.

Method Summary

Modifier and Type Method Description
Component add(Component c)
Appends a component to the end of this menu.
Component add(Component c, int index)
Adds the specified component to this container at the given position.
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)
Creates a new menu item attached to the specified Action object and appends it to the end of this menu.
JMenuItem add(JMenuItem menuItem)
Appends a menu item to the end of this menu.
void addMenuListener(MenuListener l)
Adds a listener for menu events.
void addSeparator()
Appends a new separator to the end of the menu.
void applyComponentOrientation(ComponentOrientation o)
Sets the ComponentOrientation property of this menu and all components contained within it.
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 JMenu.
protected JMenu.WinListener createWinListener(JPopupMenu p)
Creates a window-closing listener for the popup.
void doClick(int pressTime)
Programmatically performs a "click".
protected void fireMenuCanceled()
Notifies all listeners that have registered interest for notification on this event type.
protected void fireMenuDeselected()
Notifies all listeners that have registered interest for notification on this event type.
protected void fireMenuSelected()
Notifies all listeners that have registered interest for notification on this event type.
AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this JMenu.
Component getComponent()
Returns the java.awt.Component used to paint this MenuElement.
int getDelay()
Returns the suggested delay, in milliseconds, before submenus are popped up or down.
JMenuItem getItem(int pos)
Returns the JMenuItem at the specified position.
int getItemCount()
Returns the number of items on the menu, including separators.
Component getMenuComponent(int n)
Returns the component at position n.
int getMenuComponentCount()
Returns the number of components on the menu.
Component[] getMenuComponents()
Returns an array of Components of the menu's subcomponents.
MenuListener[] getMenuListeners()
Returns an array of all the MenuListeners added to this JMenu with addMenuListener().
JPopupMenu getPopupMenu()
Returns the popupmenu associated with this menu.
protected Point getPopupMenuOrigin()
Computes the origin for the JMenu's popup menu.
MenuElement[] getSubElements()
Returns an array of MenuElements containing the submenu for this menu component.
String getUIClassID()
Returns the name of the L&F class that renders this component.
void insert(String s, int pos)
Inserts a new menu item with the specified text at a given position.
JMenuItem insert(Action a, int pos)
Inserts a new menu item attached to the specified Action object at a given position.
JMenuItem insert(JMenuItem mi, int pos)
Inserts the specified JMenuitem at a given position.
void insertSeparator(int index)
Inserts a separator at the specified position.
boolean isMenuComponent(Component c)
Returns true if the specified component exists in the submenu hierarchy.
boolean isPopupMenuVisible()
Returns true if the menu's popup window is visible.
boolean isSelected()
Returns true if the menu is currently selected (highlighted).
boolean isTearOff()
Returns true if the menu can be torn off.
boolean isTopLevelMenu()
Returns true if the menu is a 'top-level menu', that is, if it is the direct child of a menubar.
void menuSelectionChanged(boolean isIncluded)
Messaged when the menubar selection changes to activate or deactivate this menu.
protected String paramString()
Returns a string representation of this JMenu.
protected void processKeyEvent(KeyEvent evt)
Processes key stroke events such as mnemonics and accelerators.
void remove(int pos)
Removes the menu item at the specified index from this menu.
void remove(Component c)
Removes the component c from this menu.
void remove(JMenuItem item)
Removes the specified menu item from this menu.
void removeAll()
Removes all menu items from this menu.
void removeMenuListener(MenuListener l)
Removes a listener for menu events.
void setAccelerator(KeyStroke keyStroke)
setAccelerator is not defined for JMenu.
void setComponentOrientation(ComponentOrientation o)
Sets the orientation for this menu and its associated popup menu determined by the ComponentOrientation argument.
void setDelay(int d)
Sets the suggested delay before the menu's PopupMenu is popped up or down.
void setMenuLocation(int x, int y)
Sets the location of the popup component.
void setModel(ButtonModel newModel)
Sets the data model for the "menu button" -- the label that the user clicks to open or close the menu.
void setPopupMenuVisible(boolean b)
Sets the visibility of the menu's popup.
void setSelected(boolean b)
Sets the selection status of the menu.
void updateUI()
Resets the UI property with a value from the current look and feel.

Methods declared in class javax.swing.JMenuItem

actionPropertyChanged, addMenuDragMouseListener, addMenuKeyListener, configurePropertiesFromAction, fireMenuDragMouseDragged, fireMenuDragMouseEntered, fireMenuDragMouseExited, fireMenuDragMouseReleased, fireMenuKeyPressed, fireMenuKeyReleased, fireMenuKeyTyped, getAccelerator, getMenuDragMouseListeners, getMenuKeyListeners, init, isArmed, processKeyEvent, processMenuDragMouseEvent, processMenuKeyEvent, processMouseEvent, removeMenuDragMouseListener, removeMenuKeyListener, setArmed, setEnabled, setUI

Methods declared in class javax.swing.AbstractButton

addActionListener, addChangeListener, addImpl, addItemListener, checkHorizontalKey, checkVerticalKey, createActionListener, createActionPropertyChangeListener, createChangeListener, createItemListener, doClick, fireActionPerformed, fireItemStateChanged, fireStateChanged, getAction, getActionCommand, getActionListeners, getChangeListeners, getDisabledIcon, getDisabledSelectedIcon, getDisplayedMnemonicIndex, getHideActionText, getHorizontalAlignment, getHorizontalTextPosition, getIcon, getIconTextGap, getItemListeners, getLabel, getMargin, getMnemonic, getModel, getMultiClickThreshhold, getPressedIcon, getRolloverIcon, getRolloverSelectedIcon, getSelectedIcon, getSelectedObjects, getText, getUI, getVerticalAlignment, getVerticalTextPosition, imageUpdate, isBorderPainted, isContentAreaFilled, isFocusPainted, isRolloverEnabled, paintBorder, removeActionListener, removeChangeListener, removeItemListener, removeNotify, setAction, setActionCommand, setBorderPainted, setContentAreaFilled, setDisabledIcon, setDisabledSelectedIcon, setDisplayedMnemonicIndex, setFocusPainted, setHideActionText, setHorizontalAlignment, setHorizontalTextPosition, setIcon, setIconTextGap, setLabel, setLayout, setMargin, setMnemonic, setMnemonic, setMultiClickThreshhold, setPressedIcon, setRolloverEnabled, setRolloverIcon, setRolloverSelectedIcon, setSelectedIcon, setText, setUI, setVerticalAlignment, setVerticalTextPosition

Methods declared in class javax.swing.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, hide, 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, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update

Methods declared in class java.awt.Container

add, add, add, addContainerListener, addPropertyChangeListener, addPropertyChangeListener, 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, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, transferFocusDownCycle, validate, validateTree

Methods declared in class java.awt.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, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, 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, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setMixingCutoutShape, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods declared in class java.lang.Object

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

Methods declared in interface javax.swing.MenuElement

processKeyEvent, processMouseEvent

Field Details

popupListener

protected JMenu.WinListener popupListener
The window-closing listener for the popup.
See Also:

Constructor Details

JMenu

public JMenu()
Constructs a new JMenu with no text.

JMenu

public JMenu(String s)
Constructs a new JMenu with the supplied string as its text.
Parameters:
s - the text for the menu label

JMenu

public JMenu(Action a)
Constructs a menu whose properties are taken from the Action supplied.
Parameters:
a - an Action
Since:
1.3

JMenu

public JMenu(String s, boolean b)
Constructs a new JMenu with the supplied string as its text and specified as a tear-off menu or not.
Parameters:
s - the text for the menu label
b - can the menu be torn off (not yet implemented)

Method Details

updateUI

public void updateUI()
Resets the UI property with a value from the current look and feel.
Overrides:
updateUI in class JMenuItem
See Also:

getUIClassID

@BeanProperty(bound=false) public String getUIClassID()
Returns the name of the L&F class that renders this component.
Overrides:
getUIClassID in class JMenuItem
Returns:
the string "MenuUI"
See Also:

setModel

public void setModel(ButtonModel newModel)
Sets the data model for the "menu button" -- the label that the user clicks to open or close the menu.
Overrides:
setModel in class AbstractButton
Parameters:
newModel - the ButtonModel
See Also:

isSelected

public boolean isSelected()
Returns true if the menu is currently selected (highlighted).
Overrides:
isSelected in class AbstractButton
Returns:
true if the menu is selected, else false

setSelected

@BeanProperty(expert=true, hidden=true, description="When the menu is selected, its popup child is shown.") public void setSelected(boolean b)
Sets the selection status of the menu.
Overrides:
setSelected in class AbstractButton
Parameters:
b - true to select (highlight) the menu; false to de-select the menu

isPopupMenuVisible

public boolean isPopupMenuVisible()
Returns true if the menu's popup window is visible.
Returns:
true if the menu is visible, else false

setPopupMenuVisible

@BeanProperty(bound=false, expert=true, hidden=true, description="The popup menu\'s visibility") public void setPopupMenuVisible(boolean b)
Sets the visibility of the menu's popup. If the menu is not enabled, this method will have no effect.
Parameters:
b - a boolean value -- true to make the menu visible, false to hide it

getPopupMenuOrigin

protected Point getPopupMenuOrigin()
Computes the origin for the JMenu's popup menu. This method uses Look and Feel properties named Menu.menuPopupOffsetX, Menu.menuPopupOffsetY, Menu.submenuPopupOffsetX, and Menu.submenuPopupOffsetY to adjust the exact location of popup.
Returns:
a Point in the coordinate space of the menu which should be used as the origin of the JMenu's popup menu
Since:
1.3

getDelay

public int getDelay()
Returns the suggested delay, in milliseconds, before submenus are popped up or down. Each look and feel (L&F) may determine its own policy for observing the delay property. In most cases, the delay is not observed for top level menus or while dragging. The default for delay is 0. This method is a property of the look and feel code and is used to manage the idiosyncrasies of the various UI implementations.
Returns:
the delay property

setDelay

@BeanProperty(bound=false, expert=true, description="The delay between menu selection and making the popup menu visible") public void setDelay(int d)
Sets the suggested delay before the menu's PopupMenu is popped up or down. Each look and feel (L&F) may determine it's own policy for observing the delay property. In most cases, the delay is not observed for top level menus or while dragging. This method is a property of the look and feel code and is used to manage the idiosyncrasies of the various UI implementations.
Parameters:
d - the number of milliseconds to delay
Throws:
IllegalArgumentException - if d is less than 0

setMenuLocation

public void setMenuLocation(int x, int y)
Sets the location of the popup component.
Parameters:
x - the x coordinate of the popup's new position
y - the y coordinate of the popup's new position

add

public JMenuItem add(JMenuItem menuItem)
Appends a menu item to the end of this menu. Returns the menu item added.
Parameters:
menuItem - the JMenuitem to be added
Returns:
the JMenuItem added

add

public Component add(Component c)
Appends a component to the end of this menu. Returns the component added.
Overrides:
add in class Container
Parameters:
c - the Component to add
Returns:
the Component added
See Also:

add

public Component add(Component c, int index)
Adds the specified component to this container at the given position. If index equals -1, the component will be appended to the end.
Overrides:
add in class Container
Parameters:
c - the Component to add
index - the position at which to insert the component
Returns:
the Component added
See Also:

add

public JMenuItem add(String s)
Creates a new menu item with the specified text and appends it to the end of this menu.
Parameters:
s - the string for the menu item to be added
Returns:
the new JMenuItem

add

public JMenuItem add(Action a)
Creates a new menu item attached to the specified Action object and appends it to the end of this menu.
Parameters:
a - the Action for the menu item to be added
Returns:
the new JMenuItem
See Also:

createActionComponent

protected JMenuItem createActionComponent(Action a)
Factory method which creates the JMenuItem for Actions added to the JMenu.
Parameters:
a - the Action for the menu item to be added
Returns:
the new menu item
Since:
1.3
See Also:

createActionChangeListener

protected PropertyChangeListener createActionChangeListener(JMenuItem b)
Returns a properly configured PropertyChangeListener which updates the control as changes to the Action occur.
Parameters:
b - a menu item for which to create a PropertyChangeListener
Returns:
a PropertyChangeListener for b

addSeparator

public void addSeparator()
Appends a new separator to the end of the menu.

insert

public void insert(String s, int pos)
Inserts a new menu item with the specified text at a given position.
Parameters:
s - the text for the menu item to add
pos - an integer specifying the position at which to add the new menu item
Throws:
IllegalArgumentException - when the value of pos < 0

insert

public JMenuItem insert(JMenuItem mi, int pos)
Inserts the specified JMenuitem at a given position.
Parameters:
mi - the JMenuitem to add
pos - an integer specifying the position at which to add the new JMenuitem
Returns:
the new menu item
Throws:
IllegalArgumentException - if the value of pos < 0

insert

public JMenuItem insert(Action a, int pos)
Inserts a new menu item attached to the specified Action object at a given position.
Parameters:
a - the Action object for the menu item to add
pos - an integer specifying the position at which to add the new menu item
Returns:
the new menu item
Throws:
IllegalArgumentException - if the value of pos < 0

insertSeparator

public void insertSeparator(int index)
Inserts a separator at the specified position.
Parameters:
index - an integer specifying the position at which to insert the menu separator
Throws:
IllegalArgumentException - if the value of index < 0

getItem

public JMenuItem getItem(int pos)
Returns the JMenuItem at the specified position. If the component at pos is not a menu item, null is returned. This method is included for AWT compatibility.
Parameters:
pos - an integer specifying the position
Returns:
the menu item at the specified position; or null if the item as the specified position is not a menu item
Throws:
IllegalArgumentException - if the value of pos < 0

getItemCount

@BeanProperty(bound=false) public int getItemCount()
Returns the number of items on the menu, including separators. This method is included for AWT compatibility.
Returns:
an integer equal to the number of items on the menu
See Also:

isTearOff

@BeanProperty(bound=false) public boolean isTearOff()
Returns true if the menu can be torn off. This method is not yet implemented.
Returns:
true if the menu can be torn off, else false
Throws:
Error - if invoked -- this method is not yet implemented

remove

public void remove(JMenuItem item)
Removes the specified menu item from this menu. If there is no popup menu, this method will have no effect.
Parameters:
item - the JMenuItem to be removed from the menu

remove

public void remove(int pos)
Removes the menu item at the specified index from this menu.
Overrides:
remove in class Container
Parameters:
pos - the position of the item to be removed
Throws:
IllegalArgumentException - if the value of pos < 0, or if pos is greater than the number of menu items
See Also:

remove

public void remove(Component c)
Removes the component c from this menu.
Overrides:
remove in class Container
Parameters:
c - the component to be removed
See Also:

removeAll

public void removeAll()
Removes all menu items from this menu.
Overrides:
removeAll in class Container
See Also:

getMenuComponentCount

@BeanProperty(bound=false) public int getMenuComponentCount()
Returns the number of components on the menu.
Returns:
an integer containing the number of components on the menu

getMenuComponent

public Component getMenuComponent(int n)
Returns the component at position n.
Parameters:
n - the position of the component to be returned
Returns:
the component requested, or null if there is no popup menu

getMenuComponents

@BeanProperty(bound=false) public Component[] getMenuComponents()
Returns an array of Components of the menu's subcomponents. Note that this returns all Components in the popup menu, including separators.
Returns:
an array of Components or an empty array if there is no popup menu

isTopLevelMenu

@BeanProperty(bound=false) public boolean isTopLevelMenu()
Returns true if the menu is a 'top-level menu', that is, if it is the direct child of a menubar.
Returns:
true if the menu is activated from the menu bar; false if the menu is activated from a menu item on another menu

isMenuComponent

public boolean isMenuComponent(Component c)
Returns true if the specified component exists in the submenu hierarchy.
Parameters:
c - the Component to be tested
Returns:
true if the Component exists, false otherwise

getPopupMenu

@BeanProperty(bound=false) public JPopupMenu getPopupMenu()
Returns the popupmenu associated with this menu. If there is no popupmenu, it will create one.
Returns:
the JPopupMenu associated with this menu

addMenuListener

public void addMenuListener(MenuListener l)
Adds a listener for menu events.
Parameters:
l - the listener to be added

removeMenuListener

public void removeMenuListener(MenuListener l)
Removes a listener for menu events.
Parameters:
l - the listener to be removed

getMenuListeners

@BeanProperty(bound=false) public MenuListener[] getMenuListeners()
Returns an array of all the MenuListeners added to this JMenu with addMenuListener().
Returns:
all of the MenuListeners added or an empty array if no listeners have been added
Since:
1.4

fireMenuSelected

protected void fireMenuSelected()
Notifies all listeners that have registered interest for notification on this event type. The event instance is created lazily.
Throws:
Error - if there is a null listener
See Also:

fireMenuDeselected

protected void fireMenuDeselected()
Notifies all listeners that have registered interest for notification on this event type. The event instance is created lazily.
Throws:
Error - if there is a null listener
See Also:

fireMenuCanceled

protected void fireMenuCanceled()
Notifies all listeners that have registered interest for notification on this event type. The event instance is created lazily.
Throws:
Error - if there is a null listener
See Also:

createWinListener

protected JMenu.WinListener createWinListener(JPopupMenu p)
Creates a window-closing listener for the popup.
Parameters:
p - the JPopupMenu
Returns:
the new window-closing listener
See Also:

getSubElements

@BeanProperty(bound=false) public MenuElement[] getSubElements()
Returns an array of MenuElements containing the submenu for this menu component. If popup menu is null returns an empty array. This method is required to conform to the MenuElement interface. Note that since JSeparators do not conform to the MenuElement interface, this array will only contain JMenuItems.
Specified by:
getSubElements in interface MenuElement
Overrides:
getSubElements in class JMenuItem
Returns:
an array of MenuElement objects

getComponent

public Component getComponent()
Returns the java.awt.Component used to paint this MenuElement. The returned component is used to convert events and detect if an event is inside a menu component.
Specified by:
getComponent in interface MenuElement
Overrides:
getComponent in class JMenuItem
Returns:
the Component that paints this menu item

applyComponentOrientation

public void applyComponentOrientation(ComponentOrientation o)
Sets the ComponentOrientation property of this menu and all components contained within it. This includes all components returned by getMenuComponents.
Overrides:
applyComponentOrientation in class Container
Parameters:
o - the new component orientation of this menu and the components contained within it.
Throws:
NullPointerException - if orientation is null.
Since:
1.4
See Also:

setComponentOrientation

public void setComponentOrientation(ComponentOrientation o)
Sets the orientation for this menu and its associated popup menu determined by the ComponentOrientation argument.
Overrides:
setComponentOrientation in class Component
Parameters:
o - the new orientation for this menu and its associated popup menu.
See Also:

setAccelerator

public void setAccelerator(KeyStroke keyStroke)
setAccelerator is not defined for JMenu. Use setMnemonic instead.
Overrides:
setAccelerator in class JMenuItem
Parameters:
keyStroke - the keystroke combination which will invoke the JMenuItem's actionlisteners without navigating the menu hierarchy
Throws:
Error - if invoked -- this method is not defined for JMenu. Use setMnemonic instead

processKeyEvent

protected void processKeyEvent(KeyEvent evt)
Processes key stroke events such as mnemonics and accelerators.
Overrides:
processKeyEvent in class JComponent
Parameters:
evt - the key event to be processed
See Also:

doClick

public void doClick(int pressTime)
Programmatically performs a "click". This overrides the method AbstractButton.doClick in order to make the menu pop up.
Overrides:
doClick in class AbstractButton
Parameters:
pressTime - indicates the number of milliseconds the button was pressed for

paramString

protected String paramString()
Returns a string representation of this JMenu. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.
Overrides:
paramString in class JMenuItem
Returns:
a string representation of this JMenu.

getAccessibleContext

@BeanProperty(bound=false) public AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this JMenu. For JMenus, the AccessibleContext takes the form of an AccessibleJMenu. A new AccessibleJMenu instance is created if necessary.
Specified by:
getAccessibleContext in interface Accessible
Overrides:
getAccessibleContext in class JMenuItem
Returns:
an AccessibleJMenu that serves as the AccessibleContext of this JMenu

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https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/javax/swing/JMenu.html