Class JLayer<V extends Component>

javax.swing.JLayer<V>

Type Parameters:: V - the type of JLayer's view component

All Implemented Interfaces:: ImageObserver, MenuContainer, PropertyChangeListener, Serializable, EventListener, Accessible, Scrollable

public final class JLayer<V extends Component> extends JComponent implements Scrollable, PropertyChangeListener, Accessible

JLayer is a universal decorator for Swing components which enables you to implement various advanced painting effects as well as receive notifications of all AWTEvents generated within its borders.

JLayer delegates the handling of painting and input events to a LayerUI object, which performs the actual decoration.

The custom painting implemented in the LayerUI and events notification work for the JLayer itself and all its subcomponents. This combination enables you to enrich existing components by adding new advanced functionality such as temporary locking of a hierarchy, data tips for compound components, enhanced mouse scrolling etc and so on.

JLayer is a good solution if you only need to do custom painting over compound component or catch input events from its subcomponents.

import javax.swing.*;
import javax.swing.plaf.LayerUI;
import java.awt.*;

public class JLayerSample {

    private static JLayer<JComponent> createLayer() {
        // This custom layerUI will fill the layer with translucent green
        // and print out all mouseMotion events generated within its borders
        LayerUI<JComponent> layerUI = new LayerUI<JComponent>() {

            public void paint(Graphics g, JComponent c) {
                // paint the layer as is
                super.paint(g, c);
                // fill it with the translucent green
                g.setColor(new Color(0, 128, 0, 128));
                g.fillRect(0, 0, c.getWidth(), c.getHeight());
            }

            public void installUI(JComponent c) {
                super.installUI(c);
                // enable mouse motion events for the layer's subcomponents
                ((JLayer) c).setLayerEventMask(AWTEvent.MOUSE_MOTION_EVENT_MASK);
            }

            public void uninstallUI(JComponent c) {
                super.uninstallUI(c);
                // reset the layer event mask
                ((JLayer) c).setLayerEventMask(0);
            }

            // overridden method which catches MouseMotion events
            public void eventDispatched(AWTEvent e, JLayer<? extends JComponent> l) {
                System.out.println("AWTEvent detected: " + e);
            }
        };
        // create a component to be decorated with the layer
        JPanel panel = new JPanel();
        panel.add(new JButton("JButton"));

        // create the layer for the panel using our custom layerUI
        return new JLayer<JComponent>(panel, layerUI);
    }

    private static void createAndShowGUI() {
        final JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        // work with the layer as with any other Swing component
        frame.add(createLayer());

        frame.setSize(200, 200);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) throws Exception {
        SwingUtilities.invokeAndWait(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

Note: JLayer doesn't support the following methods:

using any of them will cause UnsupportedOperationException to be thrown, to add a component to JLayer use setView(Component) or setGlassPane(JPanel).

Since:

1.7

See Also:

Nested Class Summary

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 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

Constructor	Description
`JLayer()`	Creates a new `JLayer` object with a `null` view component and default `LayerUI`.
`JLayer(V view)`	Creates a new `JLayer` object with default `LayerUI`.
`JLayer(V view, LayerUI<V> ui)`	Creates a new `JLayer` object with the specified view component and `LayerUI` object.

Method Summary

Modifier and Type	Method	Description
`protected void`	`addImpl(Component comp, Object constraints, int index)`	This method is not supported by `JLayer` and always throws `UnsupportedOperationException`
`JPanel`	`createGlassPane()`	Called by the constructor methods to create a default `glassPane`.
`void`	`doLayout()`	Delegates its functionality to the `LayerUI.doLayout(JLayer)` method, if `LayerUI` is set.
`AccessibleContext`	`getAccessibleContext()`	Gets the AccessibleContext associated with this `JLayer`.
`Border`	`getBorder()`	Delegates its functionality to the `getView().getBorder()` method, if the view component is an instance of `javax.swing.JComponent`, otherwise returns `null`.
`JPanel`	`getGlassPane()`	Returns the `JLayer`'s glassPane component or `null`.
`long`	`getLayerEventMask()`	Returns the bitmap of event mask to receive by this `JLayer` and its `LayerUI`.
`Dimension`	`getPreferredScrollableViewportSize()`	Returns the preferred size of the viewport for a view component.
`int`	`getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)`	Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one block of rows or columns, depending on the value of orientation.
`boolean`	`getScrollableTracksViewportHeight()`	Returns `false` to indicate that the height of the viewport does not determine the height of the layer, unless the preferred height of the layer is smaller than the height of the viewport.
`boolean`	`getScrollableTracksViewportWidth()`	Returns `false` to indicate that the width of the viewport does not determine the width of the layer, unless the preferred width of the layer is smaller than the width of the viewport.
`int`	`getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)`	Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one new row or column, depending on the value of orientation.
`LayerUI<? super V>`	`getUI()`	Returns the `LayerUI` for this `JLayer`.
`V`	`getView()`	Returns the `JLayer`'s view component or `null`.
`boolean`	`imageUpdate(Image img, int infoflags, int x, int y, int w, int h)`	Delegates its functionality to the `LayerUI.imageUpdate(java.awt.Image, int, int, int, int, int, JLayer)` method, if the `LayerUI` is set.
`boolean`	`isOptimizedDrawingEnabled()`	The `JLayer` overrides the default implementation of this method (in `JComponent`) to return `false`.
`protected boolean`	`isPaintingOrigin()`	Always returns `true` to cause painting to originate from `JLayer`, or one of its ancestors.
`void`	`paint(Graphics g)`	Delegates all painting to the `LayerUI` object.
`protected void`	`paintComponent(Graphics g)`	This method is empty, because all painting is done by `paint(Graphics)` and `ComponentUI.update(Graphics, JComponent)` methods
`void`	`paintImmediately(int x, int y, int w, int h)`	Delegates its functionality to the `LayerUI.paintImmediately(int, int, int, int, JLayer)` method, if `LayerUI` is set.
`void`	`propertyChange(PropertyChangeEvent evt)`	This method gets called when a bound property is changed.
`void`	`setBorder(Border border)`	Delegates its functionality to the `getView().setBorder(Border)` method, if the view component is an instance of `javax.swing.JComponent`, otherwise this method is a no-op.
`void`	`setGlassPane(JPanel glassPane)`	Sets the `JLayer`'s glassPane component, which can be `null`.
`void`	`setLayerEventMask(long layerEventMask)`	Enables the events from JLayer and all its descendants defined by the specified event mask parameter to be delivered to the `LayerUI.eventDispatched(AWTEvent, JLayer)` method.
`void`	`setLayout(LayoutManager mgr)`	Sets the layout manager for this container.
`void`	`setUI(LayerUI<? super V> ui)`	Sets the `LayerUI` which will perform painting and receive input events for this `JLayer`.
`void`	`setView(V view)`	Sets the `JLayer`'s view component, which can be `null`.
`void`	`updateUI()`	Delegates its functionality to the `LayerUI.updateUI(JLayer)` method, if `LayerUI` is set.

Methods declared in class JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, 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, getUIClassID, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isPaintingForPrint, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paintBorder, paintChildren, paintImmediately, paramString, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, 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.
`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.
`String`	`getUIClassID()`	Returns the `UIDefaults` key used to look up the name of the `swing.plaf.ComponentUI` class that defines the look and feel for this component.
`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.
`void`	`hide()`	Deprecated.
`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.
`final boolean`	`isPaintingForPrint()`	Returns `true` if the current painting operation on this component is part of a `print` operation.
`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.
`protected void`	`paintBorder(Graphics g)`	Paints the component's border.
`protected void`	`paintChildren(Graphics g)`	Paints this component's children.
`void`	`paintImmediately(Rectangle r)`	Paints the specified region now.
`protected String`	`paramString()`	Returns a string representation of this `JComponent`.
`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`	`processKeyEvent(KeyEvent e)`	Overrides `processKeyEvent` to process events.
`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`	`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`	`setVisible(boolean aFlag)`	Makes the component visible or invisible.
`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, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, 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, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, 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.
`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)`
`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(int index)`	Removes the component, specified by `index`, from 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`	`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, 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, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setMixingCutoutShape, setName, setSize, setSize, show, 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`	`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`	`isFocusTraversable()`	Deprecated. As of 1.4, replaced by `isFocusable()`.
`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`	`isVisible()`	Determines whether this component should be visible when its parent is visible.
`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(int x, int y)`	Moves this component to a new location.
`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()`	Deprecated. As of JDK version 1.1, replaced by `setVisible(boolean)`.
`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.

Constructor Details

JLayer

public JLayer()

Creates a new JLayer object with a null view component and default LayerUI.

See Also:

JLayer

public JLayer(V view)

Creates a new JLayer object with default LayerUI.

Parameters:

view - the component to be decorated by this JLayer

See Also:

JLayer

public JLayer(V view, LayerUI<V> ui)

Creates a new JLayer object with the specified view component and LayerUI object.

Parameters:: view - the component to be decorated; ui - the LayerUI delegate to be used by this JLayer

Method Details

getView

public V getView()

Returns the JLayer's view component or null.
This is a bound property.

Returns:

the JLayer's view component or null if none exists

See Also:

setView

public void setView(V view)

Sets the JLayer's view component, which can be null.
This is a bound property.

Parameters:

view - the view component for this JLayer

See Also:

setUI

public void setUI(LayerUI<? super V> ui)

Sets the LayerUI which will perform painting and receive input events for this JLayer.

Parameters:: ui - the LayerUI for this JLayer

getUI

public LayerUI<? super V> getUI()

Returns the LayerUI for this JLayer.

Overrides:: getUI in class JComponent
Returns:: the LayerUI for this JLayer

getGlassPane

public JPanel getGlassPane()

Returns the JLayer's glassPane component or null.
This is a bound property.

Returns:

the JLayer's glassPane component or null if none exists

See Also:

setGlassPane

public void setGlassPane(JPanel glassPane)

Sets the JLayer's glassPane component, which can be null.
This is a bound property.

Parameters:

glassPane - the glassPane component of this JLayer

See Also:

createGlassPane

public JPanel createGlassPane()

Called by the constructor methods to create a default glassPane. By default this method creates a new JPanel with visibility set to true and opacity set to false.

Returns:: the default glassPane

setLayout

public void setLayout(LayoutManager mgr)

Sets the layout manager for this container. This method is overridden to prevent the layout manager from being set.

Note: If mgr is non-null, this method will throw an exception as layout managers are not supported on a JLayer.

Overrides:

setLayout in class Container

Parameters:

mgr - the specified layout manager

Throws:

IllegalArgumentException - this method is not supported

See Also:

setBorder

public void setBorder(Border border)

Delegates its functionality to the getView().setBorder(Border) method, if the view component is an instance of javax.swing.JComponent, otherwise this method is a no-op.

Overrides:

setBorder in class JComponent

Parameters:

border - the border to be rendered for the view component

See Also:

getBorder

public Border getBorder()

Delegates its functionality to the getView().getBorder() method, if the view component is an instance of javax.swing.JComponent, otherwise returns null.

Overrides:

getBorder in class JComponent

Returns:

the border object for the view component

See Also:

addImpl

protected void addImpl(Component comp, Object constraints, int index)

This method is not supported by JLayer and always throws UnsupportedOperationException

Overrides:

addImpl in class Container

Parameters:

comp - the component to be added

constraints - an object expressing layout constraints for this component

index - the position in the container's list at which to insert the component, where -1 means append to the end

Throws:

UnsupportedOperationException - this method is not supported

See Also:

isPaintingOrigin

protected boolean isPaintingOrigin()

Always returns true to cause painting to originate from JLayer, or one of its ancestors.

Overrides:

isPaintingOrigin in class JComponent

Returns:

true

See Also:

paintImmediately

public void paintImmediately(int x, int y, int w, int h)

Delegates its functionality to the LayerUI.paintImmediately(int, int, int, int, JLayer) method, if LayerUI is set.

Overrides:

paintImmediately in class JComponent

Parameters:

x - the x value of the region to be painted

y - the y value of the region to be painted

w - the width of the region to be painted

h - the height of the region to be painted

See Also:

imageUpdate

public boolean imageUpdate(Image img, int infoflags, int x, int y, int w, int h)

Delegates its functionality to the LayerUI.imageUpdate(java.awt.Image, int, int, int, int, int, JLayer) method, if the LayerUI is set.

Specified by:

imageUpdate in interface ImageObserver

Overrides:

imageUpdate in class Component

Parameters:

img - the image being observed

infoflags - see imageUpdate for more information

x - the x coordinate

y - the y coordinate

w - the width

h - the height

Returns:

false if the infoflags indicate that the image is completely loaded; true otherwise.

See Also:

paint

public void paint(Graphics g)

Delegates all painting to the LayerUI object.

Overrides:

paint in class JComponent

Parameters:

g - the Graphics to render to

See Also:

paintComponent

protected void paintComponent(Graphics g)

This method is empty, because all painting is done by paint(Graphics) and ComponentUI.update(Graphics, JComponent) methods

Overrides:

paintComponent in class JComponent

Parameters:

g - the Graphics object to protect

See Also:

isOptimizedDrawingEnabled

public boolean isOptimizedDrawingEnabled()

The JLayer overrides the default implementation of this method (in JComponent) to return false. This ensures that the drawing machinery will call the JLayer's paint implementation rather than messaging the JLayer's children directly.

Overrides:: isOptimizedDrawingEnabled in class JComponent
Returns:: false

propertyChange

public void propertyChange(PropertyChangeEvent evt)

This method gets called when a bound property is changed.

Specified by:: propertyChange in interface PropertyChangeListener
Parameters:: evt - A PropertyChangeEvent object describing the event source and the property that has changed.

setLayerEventMask

public void setLayerEventMask(long layerEventMask)

Enables the events from JLayer and all its descendants defined by the specified event mask parameter to be delivered to the LayerUI.eventDispatched(AWTEvent, JLayer) method.

Events are delivered provided that LayerUI is set for this JLayer and the JLayer is displayable.

The following example shows how to correctly use this method in the LayerUI implementations:

   public void installUI(JComponent c) {
      super.installUI(c);
      JLayer l = (JLayer) c;
      // this LayerUI will receive only key and focus events
      l.setLayerEventMask(AWTEvent.KEY_EVENT_MASK | AWTEvent.FOCUS_EVENT_MASK);
   }

   public void uninstallUI(JComponent c) {
      super.uninstallUI(c);
      JLayer l = (JLayer) c;
      // JLayer must be returned to its initial state
      l.setLayerEventMask(0);
   }

By default JLayer receives no events and its event mask is 0.

Parameters:

layerEventMask - the bitmask of event types to receive

See Also:

getLayerEventMask

public long getLayerEventMask()

Returns the bitmap of event mask to receive by this JLayer and its LayerUI.

It means that LayerUI.eventDispatched(AWTEvent, JLayer) method will only receive events that match the event mask.

By default JLayer receives no events.

Returns:: the bitmask of event types to receive for this JLayer

updateUI

public void updateUI()

Delegates its functionality to the LayerUI.updateUI(JLayer) method, if LayerUI is set.

Overrides:

updateUI in class JComponent

See Also:

getPreferredScrollableViewportSize

public Dimension getPreferredScrollableViewportSize()

Returns the preferred size of the viewport for a view component.

If the view component of this layer implements Scrollable, this method delegates its implementation to the view component.

Specified by:

getPreferredScrollableViewportSize in interface Scrollable

Returns:

the preferred size of the viewport for a view component

See Also:

getScrollableBlockIncrement

public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)

Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one block of rows or columns, depending on the value of orientation.

If the view component of this layer implements Scrollable, this method delegates its implementation to the view component.

Specified by:

getScrollableBlockIncrement in interface Scrollable

Parameters:

visibleRect - The view area visible within the viewport

orientation - Either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.

direction - Less than zero to scroll up/left, greater than zero for down/right.

Returns:

the "block" increment for scrolling in the specified direction

See Also:

getScrollableTracksViewportHeight

public boolean getScrollableTracksViewportHeight()

Returns false to indicate that the height of the viewport does not determine the height of the layer, unless the preferred height of the layer is smaller than the height of the viewport.

If the view component of this layer implements Scrollable, this method delegates its implementation to the view component.

Specified by:

getScrollableTracksViewportHeight in interface Scrollable

Returns:

whether the layer should track the height of the viewport

See Also:

getScrollableTracksViewportWidth

public boolean getScrollableTracksViewportWidth()

Returns false to indicate that the width of the viewport does not determine the width of the layer, unless the preferred width of the layer is smaller than the width of the viewport.

If the view component of this layer implements Scrollable, this method delegates its implementation to the view component.

Specified by:

getScrollableTracksViewportWidth in interface Scrollable

Returns:

whether the layer should track the width of the viewport

See Also:

getScrollableUnitIncrement

public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)

Returns a scroll increment, which is required for components that display logical rows or columns in order to completely expose one new row or column, depending on the value of orientation. Ideally, components should handle a partially exposed row or column by returning the distance required to completely expose the item.

Scrolling containers, like JScrollPane, will use this method each time the user requests a unit scroll.

If the view component of this layer implements Scrollable, this method delegates its implementation to the view component.

Specified by:

getScrollableUnitIncrement in interface Scrollable

Parameters:

visibleRect - The view area visible within the viewport

orientation - Either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL.

direction - Less than zero to scroll up/left, greater than zero for down/right.

Returns:

The "unit" increment for scrolling in the specified direction. This value should always be positive.

See Also:

doLayout

public void doLayout()

Delegates its functionality to the LayerUI.doLayout(JLayer) method, if LayerUI is set.

Overrides:

doLayout in class Container

See Also:

getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this JLayer.

Specified by:: getAccessibleContext in interface Accessible
Overrides:: getAccessibleContext in class Component
Returns:: the AccessibleContext associated with this JLayer.

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