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/OpenJDK 8 GUI

Class JWindow

All Implemented Interfaces:
ImageObserver, MenuContainer, Serializable, Accessible, RootPaneContainer 
public class JWindow
extends Window
implements Accessible, RootPaneContainer

A JWindow is a container that can be displayed anywhere on the user's desktop. It does not have the title bar, window-management buttons, or other trimmings associated with a JFrame, but it is still a "first-class citizen" of the user's desktop, and can exist anywhere on it.

The JWindow component contains a JRootPane as its only child. The contentPane should be the parent of any children of the JWindow. As a convenience, the add, remove, and setLayout methods of this class are overridden, so that they delegate calls to the corresponding methods of the ContentPane. For example, you can add a child component to a window as follows: 

window.add(child);
And the child will be added to the contentPane. The contentPane will always be non-null. Attempting to set it to null will cause the JWindow to throw an exception. The default contentPane will have a BorderLayout manager set on it. Refer to RootPaneContainer for details on adding, removing and setting the LayoutManager of a JWindow.

Please see the JRootPane documentation for a complete description of the contentPane, glassPane, and layeredPane components.

In a multi-screen environment, you can create a JWindow on a different screen device. See Window for more information.

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.

See Also:
JRootPane

Nested Classes

Nested Classes
Modifier and Type Class and Description
protected class  JWindow.AccessibleJWindow

This class implements accessibility support for the JWindow class.

Nested classes/interfaces inherited from class java.awt.Window

Window.AccessibleAWTWindow, Window.Type

Nested classes/interfaces inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

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

Fields

rootPane

protected JRootPane rootPane

The JRootPane instance that manages the contentPane and optional menuBar for this frame, as well as the glassPane.

See Also:
getRootPane(), setRootPane(javax.swing.JRootPane)

rootPaneCheckingEnabled

protected boolean rootPaneCheckingEnabled

If true then calls to add and setLayout will be forwarded to the contentPane. This is initially false, but is set to true when the JWindow is constructed.

See Also:
isRootPaneCheckingEnabled(), setRootPaneCheckingEnabled(boolean), RootPaneContainer

accessibleContext

protected AccessibleContext accessibleContext

The accessible context property.

Constructors

JWindow

public JWindow()

Creates a window with no specified owner. This window will not be focusable.

This constructor sets the component's locale property to the value returned by JComponent.getDefaultLocale.

Throws:
HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
See Also:
GraphicsEnvironment.isHeadless(), Window.isFocusableWindow(), JComponent.getDefaultLocale()

JWindow

public JWindow(GraphicsConfiguration gc)

Creates a window with the specified GraphicsConfiguration of a screen device. This window will not be focusable.

This constructor sets the component's locale property to the value returned by JComponent.getDefaultLocale.

Parameters:
gc - the GraphicsConfiguration that is used to construct the new window with; if gc is null, the system default GraphicsConfiguration is assumed
Throws:
HeadlessException - If GraphicsEnvironment.isHeadless() returns true.
IllegalArgumentException - if gc is not from a screen device.
Since:
1.3
See Also:
GraphicsEnvironment.isHeadless(), Window.isFocusableWindow(), JComponent.getDefaultLocale()

JWindow

public JWindow(Frame owner)

Creates a window with the specified owner frame. If owner is null, the shared owner will be used and this window will not be focusable. Also, this window will not be focusable unless its owner is showing on the screen.

This constructor sets the component's locale property to the value returned by JComponent.getDefaultLocale.

Parameters:
owner - the frame from which the window is displayed
Throws:
HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
See Also:
GraphicsEnvironment.isHeadless(), Window.isFocusableWindow(), JComponent.getDefaultLocale()

JWindow

public JWindow(Window owner)

Creates a window with the specified owner window. This window will not be focusable unless its owner is showing on the screen. If owner is null, the shared owner will be used and this window will not be focusable.

This constructor sets the component's locale property to the value returned by JComponent.getDefaultLocale.

Parameters:
owner - the window from which the window is displayed
Throws:
HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
See Also:
GraphicsEnvironment.isHeadless(), Window.isFocusableWindow(), JComponent.getDefaultLocale()

JWindow

public JWindow(Window owner,
               GraphicsConfiguration gc)

Creates a window with the specified owner window and GraphicsConfiguration of a screen device. If owner is null, the shared owner will be used and this window will not be focusable.

This constructor sets the component's locale property to the value returned by JComponent.getDefaultLocale.

Parameters:
owner - the window from which the window is displayed
gc - the GraphicsConfiguration that is used to construct the new window with; if gc is null, the system default GraphicsConfiguration is assumed, unless owner is also null, in which case the GraphicsConfiguration from the shared owner frame will be used.
Throws:
HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
IllegalArgumentException - if gc is not from a screen device.
Since:
1.3
See Also:
GraphicsEnvironment.isHeadless(), Window.isFocusableWindow(), JComponent.getDefaultLocale()

Methods

windowInit

protected void windowInit()

Called by the constructors to init the JWindow properly.

createRootPane

protected JRootPane createRootPane()

Called by the constructor methods to create the default rootPane.

isRootPaneCheckingEnabled

protected boolean isRootPaneCheckingEnabled()

Returns whether calls to add and setLayout are forwarded to the contentPane.

Returns:
true if add and setLayout are forwarded; false otherwise
See Also:
addImpl(java.awt.Component, java.lang.Object, int), setLayout(java.awt.LayoutManager), setRootPaneCheckingEnabled(boolean), RootPaneContainer

setTransferHandler

public void setTransferHandler(TransferHandler newHandler)

Sets the transferHandler property, which is a mechanism to support transfer of data into this component. Use null if the component does not support data transfer operations.

If the system property suppressSwingDropSupport is false (the default) and the current drop target on this component is either null or not a user-set drop target, this method will change the drop target as follows: If newHandler is null it will clear the drop target. If not null it will install a new DropTarget.

Note: When used with JWindow, TransferHandler only provides data import capability, as the data export related methods are currently typed to JComponent.

Please see How to Use Drag and Drop and Data Transfer, a section in The Java Tutorial, for more information.

Parameters:
newHandler - the new TransferHandler
Since:
1.6
See Also:
TransferHandler, getTransferHandler(), Component.setDropTarget(java.awt.dnd.DropTarget)

getTransferHandler

public TransferHandler getTransferHandler()

Gets the transferHandler property.

Returns:
the value of the transferHandler property
Since:
1.6
See Also:
TransferHandler, setTransferHandler(javax.swing.TransferHandler)

update

public void update(Graphics g)

Calls paint(g). This method was overridden to prevent an unnecessary call to clear the background.

Overrides:
update in class Container
Parameters:
g - the Graphics context in which to paint
See Also:
Component.update(Graphics)

setRootPaneCheckingEnabled

protected void setRootPaneCheckingEnabled(boolean enabled)

Sets whether calls to add and setLayout are forwarded to the contentPane.

Parameters:
enabled - true if add and setLayout are forwarded, false if they should operate directly on the JWindow.
See Also:
addImpl(java.awt.Component, java.lang.Object, int), setLayout(java.awt.LayoutManager), isRootPaneCheckingEnabled(), RootPaneContainer

addImpl

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

Adds the specified child Component. This method is overridden to conditionally forward calls to the contentPane. By default, children are added to the contentPane instead of the frame, refer to RootPaneContainer for details.

Overrides:
addImpl in class Container
Parameters:
comp - the component to be enhanced
constraints - the constraints to be respected
index - the index
Throws:
IllegalArgumentException - if index is invalid
IllegalArgumentException - if adding the container's parent to itself
IllegalArgumentException - if adding a window to a container
See Also:
setRootPaneCheckingEnabled(boolean), RootPaneContainer

remove

public void remove(Component comp)

Removes the specified component from the container. If comp is not the rootPane, this will forward the call to the contentPane. This will do nothing if comp is not a child of the JWindow or contentPane.

Overrides:
remove in class Container
Parameters:
comp - the component to be removed
Throws:
NullPointerException - if comp is null
See Also:
Container.add(java.awt.Component), RootPaneContainer

setLayout

public void setLayout(LayoutManager manager)

Sets the LayoutManager. Overridden to conditionally forward the call to the contentPane. Refer to RootPaneContainer for more information.

Overrides:
setLayout in class Container
Parameters:
manager - the LayoutManager
See Also:
setRootPaneCheckingEnabled(boolean), RootPaneContainer

getRootPane

public JRootPane getRootPane()

Returns the rootPane object for this window.

Specified by:
getRootPane in interface RootPaneContainer
Returns:
the rootPane property for this window
See Also:
setRootPane(javax.swing.JRootPane), RootPaneContainer.getRootPane()

setRootPane

protected void setRootPane(JRootPane root)

Sets the new rootPane object for this window. This method is called by the constructor.

Parameters:
root - the new rootPane property
See Also:
getRootPane()

getContentPane

public Container getContentPane()

Returns the Container which is the contentPane for this window.

Specified by:
getContentPane in interface RootPaneContainer
Returns:
the contentPane property
See Also:
setContentPane(java.awt.Container), RootPaneContainer.getContentPane()

setContentPane

public void setContentPane(Container contentPane)

Sets the contentPane property for this window. This method is called by the constructor.

Specified by:
setContentPane in interface RootPaneContainer
Parameters:
contentPane - the new contentPane
Throws:
IllegalComponentStateException - (a runtime exception) if the content pane parameter is null
See Also:
getContentPane(), RootPaneContainer.setContentPane(java.awt.Container)

getLayeredPane

public JLayeredPane getLayeredPane()

Returns the layeredPane object for this window.

Specified by:
getLayeredPane in interface RootPaneContainer
Returns:
the layeredPane property
See Also:
setLayeredPane(javax.swing.JLayeredPane), RootPaneContainer.getLayeredPane()

setLayeredPane

public void setLayeredPane(JLayeredPane layeredPane)

Sets the layeredPane property. This method is called by the constructor.

Specified by:
setLayeredPane in interface RootPaneContainer
Parameters:
layeredPane - the new layeredPane object
Throws:
IllegalComponentStateException - (a runtime exception) if the content pane parameter is null
See Also:
getLayeredPane(), RootPaneContainer.setLayeredPane(javax.swing.JLayeredPane)

getGlassPane

public Component getGlassPane()

Returns the glassPane Component for this window.

Specified by:
getGlassPane in interface RootPaneContainer
Returns:
the glassPane property
See Also:
setGlassPane(java.awt.Component), RootPaneContainer.getGlassPane()

setGlassPane

public void setGlassPane(Component glassPane)

Sets the glassPane property. This method is called by the constructor.

Specified by:
setGlassPane in interface RootPaneContainer
Parameters:
glassPane - the glassPane object for this window
See Also:
getGlassPane(), RootPaneContainer.setGlassPane(java.awt.Component)

getGraphics

public Graphics getGraphics()

Creates a graphics context for this component. This method will return null if this component is currently not displayable.

Overrides:
getGraphics in class Component
Returns:
a graphics context for this component, or null if it has none
Since:
1.6
See Also:
Component.paint(java.awt.Graphics)

repaint

public void repaint(long time,
                    int x,
                    int y,
                    int width,
                    int height)

Repaints the specified rectangle of this component within time milliseconds. Refer to RepaintManager for details on how the repaint is handled.

Overrides:
repaint in class Component
Parameters:
time - maximum time in milliseconds before update
x - the x coordinate
y - the y coordinate
width - the width
height - the height
Since:
1.6
See Also:
RepaintManager

paramString

protected String paramString()

Returns a string representation of this JWindow. 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 Container
Returns:
a string representation of this JWindow

getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this JWindow. For JWindows, the AccessibleContext takes the form of an AccessibleJWindow. A new AccessibleJWindow instance is created if necessary.

Specified by:
getAccessibleContext in interface Accessible
Overrides:
getAccessibleContext in class Window
Returns:
an AccessibleJWindow that serves as the AccessibleContext of this JWindow

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