javax.swing
Class JFrame

java.lang.Object
  extended byjava.awt.Component
      extended byjava.awt.Container
          extended byjava.awt.Window
              extended byjava.awt.Frame
                  extended byjavax.swing.JFrame
All Implemented Interfaces:
javax.accessibility.Accessible, java.awt.image.ImageObserver, java.awt.MenuContainer, javax.swing.RootPaneContainer, java.io.Serializable, javax.swing.WindowConstants

public class JFrame
extends java.awt.Frame
implements javax.swing.WindowConstants, javax.accessibility.Accessible, javax.swing.RootPaneContainer

An extended version of java.awt.Frame that adds support for interposing input and painting behavior in front of the frame's children (see glassPane), support for special children that are managed by a LayeredPane (see rootPane) and for Swing MenuBars.

The JFrame class is slightly incompatible with java.awt.Frame. JFrame contains a JRootPane as it's only child. The contentPane should be the parent of any children of the JFrame. This is different than java.awt.Frame, e.g. to add a child to an AWT Frame you'd write:

       frame.add(child);
 
However using JFrame you need to add the child to the JFrames contentPane instead:
       frame.getContentPane().add(child);
 
The same is true for setting LayoutManagers, removing components, listing children, etc. All these methods should normally be sent to the contentPane() instead of the JFrame itself. The contentPane() will always be non-null. Attempting to set it to null will cause the JFrame to throw an exception. The default contentPane() will have a BorderLayout manager set on it.

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

Unlike its parent class, java.awt.Frame, you can tell a JFrame how to respond when the user attempts to close the window. The default behavior is to simply hide the JFrame when the user closes the window. To change the default behavior, you invoke the method setDefaultCloseOperation. To make the JFrame remain open unless you handle the window-closing event and explicitly invoke dispose() (or exit the app, which is also pretty effective), use setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE). That makes the JFrame behave the same as java.awt.Frame. A third option lets you completely dispose of the window when it closes, instead of merely hiding it.

For the keyboard keys used by this component in the standard Look and Feel (L&F) renditions, see the JFrame key assignments.

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. A future release of Swing will provide support for long term persistence.

Version:
1.59 09/29/98
Author:
Jeff Dinkins, Georges Saab, David Kloba
See Also:
JRootPane, setDefaultCloseOperation(int), WindowListener.windowClosing(java.awt.event.WindowEvent), Serialized Form

Nested Class Summary
protected  class JFrame.AccessibleJFrame
          The class used to obtain the AccessibleRole for this object.
 
Nested classes inherited from class java.awt.Frame
java.awt.Frame.AccessibleAWTFrame
 
Nested classes inherited from class java.awt.Window
java.awt.Window.AccessibleAWTWindow
 
Nested classes inherited from class java.awt.Container
java.awt.Container.AccessibleAWTContainer
 
Nested classes inherited from class java.awt.Component
java.awt.Component.AccessibleAWTComponent, java.awt.Component.BltBufferStrategy, java.awt.Component.FlipBufferStrategy
 
Field Summary
protected  javax.accessibility.AccessibleContext accessibleContext
          The accessible context property
protected  javax.swing.JRootPane rootPane
          The JRootPane instance that manages the contentPane and optional menuBar for this frame, as well as the glassPane.
protected  boolean rootPaneCheckingEnabled
          If true then calls to add and setLayout cause an exception to be thrown.
 
Fields inherited from class java.awt.Frame
CROSSHAIR_CURSOR, DEFAULT_CURSOR, E_RESIZE_CURSOR, HAND_CURSOR, ICONIFIED, MAXIMIZED_BOTH, MAXIMIZED_HORIZ, MAXIMIZED_VERT, MOVE_CURSOR, N_RESIZE_CURSOR, NE_RESIZE_CURSOR, NORMAL, NW_RESIZE_CURSOR, S_RESIZE_CURSOR, SE_RESIZE_CURSOR, SW_RESIZE_CURSOR, TEXT_CURSOR, W_RESIZE_CURSOR, WAIT_CURSOR
 
Fields inherited from class java.awt.Component
BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
 
Fields inherited from interface javax.swing.WindowConstants
DISPOSE_ON_CLOSE, DO_NOTHING_ON_CLOSE, EXIT_ON_CLOSE, HIDE_ON_CLOSE
 
Fields inherited from interface java.awt.image.ImageObserver
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH
 
Constructor Summary
JFrame()
          Constructs a new Frame that is initially invisible.
JFrame(java.lang.String title)
          Constructs a new, initially invisible Frame with the specified title.
 
Method Summary
protected  void addImpl(java.awt.Component comp, java.lang.Object constraints, int index)
          By default, children may not be added directly to a this component, they must be added to its contentPane instead.
protected  javax.swing.JRootPane createRootPane()
          Called by the constructor methods to create the default rootPane.
protected  void frameInit()
          Called by the constructors to init the JFrame properly.
 javax.accessibility.AccessibleContext getAccessibleContext()
          Get the AccessibleContext associated with this JFrame
 java.awt.Container getContentPane()
          Returns the contentPane object for this frame.
 int getDefaultCloseOperation()
          Returns the operation which occurs when the user initiates a "close" on this frame.
 java.awt.Component getGlassPane()
          Returns the glassPane object for this frame.
 javax.swing.JMenuBar getJMenuBar()
          Returns the menubar set on this frame.
 javax.swing.JLayeredPane getLayeredPane()
          Returns the layeredPane object for this frame.
 javax.swing.JRootPane getRootPane()
          Returns the rootPane object for this frame.
protected  boolean isRootPaneCheckingEnabled()
          Returns whether calls to add and setLayout cause an exception to be thrown.
protected  java.lang.String paramString()
          Returns a string representation of this JFrame.
protected  void processKeyEvent(java.awt.event.KeyEvent e)
          Processes key events occurring on this component and, if appropriate, passes them on to components in the frame which have registered interest in them.
protected  void processWindowEvent(java.awt.event.WindowEvent e)
          Processes window events occurring on this component.
 void setContentPane(java.awt.Container contentPane)
          Sets the contentPane property.
 void setDefaultCloseOperation(int operation)
          Sets the operation which will happen by default when the user initiates a "close" on this frame.
 void setGlassPane(java.awt.Component glassPane)
          Sets the glassPane property.
 void setJMenuBar(javax.swing.JMenuBar menubar)
          Sets the menubar for this frame.
 void setLayeredPane(javax.swing.JLayeredPane layeredPane)
          Sets the layeredPane property.
 void setLayout(java.awt.LayoutManager manager)
          By default the layout of this component may not be set, the layout of its contentPane should be set instead.
protected  void setRootPane(javax.swing.JRootPane root)
          Sets the rootPane property.
protected  void setRootPaneCheckingEnabled(boolean enabled)
          Determines whether calls to add and setLayout cause an exception to be thrown.
 void update(java.awt.Graphics g)
          Just calls paint(g).
 
Methods inherited from class java.awt.Frame
addNotify, finalize, getCursorType, getExtendedState, getFrames, getIconImage, getMaximizedBounds, getMenuBar, getState, getTitle, isResizable, isUndecorated, remove, removeNotify, setCursor, setExtendedState, setIconImage, setMaximizedBounds, setMenuBar, setResizable, setState, setTitle, setUndecorated
 
Methods inherited from class java.awt.Window
addPropertyChangeListener, addPropertyChangeListener, addWindowFocusListener, addWindowListener, addWindowStateListener, applyResourceBundle, applyResourceBundle, createBufferStrategy, createBufferStrategy, dispose, getBufferStrategy, getFocusableWindowState, getFocusCycleRootAncestor, getFocusOwner, getFocusTraversalKeys, getGraphicsConfiguration, getInputContext, getListeners, getLocale, getMostRecentFocusOwner, getOwnedWindows, getOwner, getToolkit, getWarningString, getWindowFocusListeners, getWindowListeners, getWindowStateListeners, hide, isActive, isFocusableWindow, isFocusCycleRoot, isFocused, isShowing, pack, postEvent, processEvent, processWindowFocusEvent, processWindowStateEvent, removeWindowFocusListener, removeWindowListener, removeWindowStateListener, setCursor, setFocusableWindowState, setFocusCycleRoot, setLocationRelativeTo, show, toBack, toFront
 
Methods inherited from class java.awt.Container
add, add, add, add, add, addContainerListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getContainerListeners, getFocusTraversalPolicy, getInsets, getLayout, getMaximumSize, getMinimumSize, getPreferredSize, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paint, paintComponents, preferredSize, print, printComponents, processContainerEvent, remove, remove, removeAll, removeContainerListener, setFocusTraversalKeys, setFocusTraversalPolicy, setFont, transferFocusBackward, transferFocusDownCycle, validate, validateTree
 
Methods inherited from class java.awt.Component
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isOpaque, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, size, toString, transferFocus, transferFocusUpCycle
 
Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface java.awt.MenuContainer
getFont, postEvent
 

Field Detail

rootPane

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

See Also:
JRootPane, RootPaneContainer

rootPaneCheckingEnabled

protected boolean rootPaneCheckingEnabled
If true then calls to add and setLayout cause an exception to be thrown.

See Also:
isRootPaneCheckingEnabled(), setRootPaneCheckingEnabled(boolean)

accessibleContext

protected javax.accessibility.AccessibleContext accessibleContext
The accessible context property

Constructor Detail

JFrame

public JFrame()
Constructs a new Frame that is initially invisible.

See Also:
Component.setSize(int, int), Component.setVisible(boolean)

JFrame

public JFrame(java.lang.String title)
Constructs a new, initially invisible Frame with the specified title.

Parameters:
title - the title for the frame
See Also:
Component.setSize(int, int), Component.setVisible(boolean)
Method Detail

frameInit

protected void frameInit()
Called by the constructors to init the JFrame properly.


createRootPane

protected javax.swing.JRootPane createRootPane()
Called by the constructor methods to create the default rootPane.


processKeyEvent

protected void processKeyEvent(java.awt.event.KeyEvent e)
Processes key events occurring on this component and, if appropriate, passes them on to components in the frame which have registered interest in them.

Parameters:
e - the key event
See Also:
Component.processKeyEvent(java.awt.event.KeyEvent)

processWindowEvent

protected void processWindowEvent(java.awt.event.WindowEvent e)
Processes window events occurring on this component. Hides the window or disposes of it, as specified by the setting of the defaultCloseOperation property.

Parameters:
e - the window event
See Also:
setDefaultCloseOperation(int), Window.processWindowEvent(java.awt.event.WindowEvent)

setDefaultCloseOperation

public void setDefaultCloseOperation(int operation)
Sets the operation which will happen by default when the user initiates a "close" on this frame. The possible choices are defined in the WindowConstants interface:

The value is set to HIDE_ON_CLOSE by default.

See Also:
Window.addWindowListener(java.awt.event.WindowListener), getDefaultCloseOperation()

getDefaultCloseOperation

public int getDefaultCloseOperation()
Returns the operation which occurs when the user initiates a "close" on this frame.

Returns:
an int indicating the window-close operation
See Also:
setDefaultCloseOperation(int)

update

public void update(java.awt.Graphics g)
Just calls paint(g). This method was overridden to prevent an unneccessary call to clear the background.

Parameters:
g - the Graphics context in which to paint

setJMenuBar

public void setJMenuBar(javax.swing.JMenuBar menubar)
Sets the menubar for this frame.

Parameters:
menubar - the menubar being placed in the frame
See Also:
getJMenuBar()

getJMenuBar

public javax.swing.JMenuBar getJMenuBar()
Returns the menubar set on this frame.

See Also:
setJMenuBar(javax.swing.JMenuBar)

isRootPaneCheckingEnabled

protected boolean isRootPaneCheckingEnabled()
Returns whether calls to add and setLayout cause an exception to be thrown.

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

setRootPaneCheckingEnabled

protected void setRootPaneCheckingEnabled(boolean enabled)
Determines whether calls to add and setLayout cause an exception to be thrown.

Parameters:
enabled - a boolean value, true if checking is to be enabled, which cause the exceptions to be thrown
See Also:
addImpl(java.awt.Component, java.lang.Object, int), setLayout(java.awt.LayoutManager), isRootPaneCheckingEnabled()

addImpl

protected void addImpl(java.awt.Component comp,
                       java.lang.Object constraints,
                       int index)
By default, children may not be added directly to a this component, they must be added to its contentPane instead. For example:
 thisComponent.getContentPane().add(child)
 
An attempt to add to directly to this component will cause an runtime exception to be thrown. Subclasses can disable this behavior.

Throws:
java.lang.Error - if called with rootPaneChecking true
See Also:
setRootPaneCheckingEnabled(boolean)

setLayout

public void setLayout(java.awt.LayoutManager manager)
By default the layout of this component may not be set, the layout of its contentPane should be set instead. For example:
 thiComponent.getContentPane().setLayout(new BorderLayout())
 
An attempt to set the layout of this component will cause an runtime exception to be thrown. Subclasses can disable this behavior.

Throws:
java.lang.Error - if called with rootPaneChecking true
See Also:
setRootPaneCheckingEnabled(boolean)

getRootPane

public javax.swing.JRootPane getRootPane()
Returns the rootPane object for this frame.

Specified by:
getRootPane in interface javax.swing.RootPaneContainer
See Also:
setRootPane(javax.swing.JRootPane), RootPaneContainer#getRootPane

setRootPane

protected void setRootPane(javax.swing.JRootPane root)
Sets the rootPane property. This method is called by the constructor.

Parameters:
root - the rootPane object for this frame
See Also:
getRootPane()

getContentPane

public java.awt.Container getContentPane()
Returns the contentPane object for this frame.

Specified by:
getContentPane in interface javax.swing.RootPaneContainer
See Also:
setContentPane(java.awt.Container), RootPaneContainer#getContentPane

setContentPane

public void setContentPane(java.awt.Container contentPane)
Sets the contentPane property. This method is called by the constructor.

Specified by:
setContentPane in interface javax.swing.RootPaneContainer
Parameters:
contentPane - the contentPane object for this frame
Throws:
java.awt.IllegalComponentStateException - (a runtime exception) if the content pane parameter is null
See Also:
getContentPane(), RootPaneContainer#setContentPane

getLayeredPane

public javax.swing.JLayeredPane getLayeredPane()
Returns the layeredPane object for this frame.

Specified by:
getLayeredPane in interface javax.swing.RootPaneContainer
See Also:
setLayeredPane(javax.swing.JLayeredPane), RootPaneContainer#getLayeredPane

setLayeredPane

public void setLayeredPane(javax.swing.JLayeredPane layeredPane)
Sets the layeredPane property. This method is called by the constructor.

Specified by:
setLayeredPane in interface javax.swing.RootPaneContainer
Parameters:
layeredPane - the layeredPane object for this frame
Throws:
java.awt.IllegalComponentStateException - (a runtime exception) if the layered pane parameter is null
See Also:
getLayeredPane(), RootPaneContainer#setLayeredPane

getGlassPane

public java.awt.Component getGlassPane()
Returns the glassPane object for this frame.

Specified by:
getGlassPane in interface javax.swing.RootPaneContainer
See Also:
setGlassPane(java.awt.Component), RootPaneContainer#getGlassPane

setGlassPane

public void setGlassPane(java.awt.Component glassPane)
Sets the glassPane property. This method is called by the constructor.

Specified by:
setGlassPane in interface javax.swing.RootPaneContainer
Parameters:
glassPane - the glassPane object for this frame
See Also:
getGlassPane(), RootPaneContainer#setGlassPane

paramString

protected java.lang.String paramString()
Returns a string representation of this JFrame. 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.

Overriding paramString() to provide information about the specific new aspects of the JFC components.

Returns:
a string representation of this JFrame.

getAccessibleContext

public javax.accessibility.AccessibleContext getAccessibleContext()
Get the AccessibleContext associated with this JFrame

Specified by:
getAccessibleContext in interface javax.accessibility.Accessible
Returns:
the AccessibleContext of this JFrame