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package javax.swing;

import java.awt.Component;
import java.awt.Container;



This interface is implemented by components that have a single
JRootPane child: JDialog, JFrame, JWindow, JApplet, JInternalFrame.
The methods in  this interface are just covers for the JRootPane
properties, e.g. getContentPane() is generally implemented
like this:
    public Container getContentPane() {
        return getRootPane().getContentPane();
    }


This interface serves as a marker for Swing GUI builders
that need to treat components like JFrame, that contain a
single JRootPane, specially.  For example in a GUI builder,
dropping a component on a RootPaneContainer would be interpreted
as frame.getContentPane().add(child).

 As a convenience, the standard classes that implement this interface (such as JFrame, JDialog, JWindow, JApplet, and JInternalFrame) have their add, remove, and setLayout methods overridden, so that they delegate calls to the corresponding methods of the ContentPane. For example, you can add a child component to a frame as follows: 
      frame.add(child);


instead of:

      frame.getContentPane().add(child);




The behavior of the add and
setLayout methods for
JFrame, JDialog, JWindow,
JApplet and JInternalFrame is controlled by
the rootPaneCheckingEnabled property. If this property is
true (the default), then calls to these methods are
forwarded to the contentPane; if false, these
methods operate directly on the RootPaneContainer. This
property is only intended for subclasses, and is therefore protected.

Author:Hans Muller
See Also:
/**
 * This interface is implemented by components that have a single
 * JRootPane child: JDialog, JFrame, JWindow, JApplet, JInternalFrame.
 * The methods in  this interface are just <i>covers</i> for the JRootPane
 * properties, e.g. <code>getContentPane()</code> is generally implemented
 * like this:<pre>
 *     public Container getContentPane() {
 *         return getRootPane().getContentPane();
 *     }
 * </pre>
 * This interface serves as a <i>marker</i> for Swing GUI builders
 * that need to treat components like JFrame, that contain a
 * single JRootPane, specially.  For example in a GUI builder,
 * dropping a component on a RootPaneContainer would be interpreted
 * as <code>frame.getContentPane().add(child)</code>.
 * <p>
 * As a convenience, the standard classes that implement this interface
 * (such as {@code JFrame}, {@code JDialog}, {@code JWindow}, {@code JApplet},
 * and {@code JInternalFrame}) have their {@code add}, {@code remove},
 * and {@code setLayout} methods overridden, so that they delegate calls
 * to the corresponding methods of the {@code ContentPane}.
 * For example, you can add a child component to a frame as follows:
 * <pre>
 *       frame.add(child);
 * </pre>
 * instead of:
 * <pre>
 *       frame.getContentPane().add(child);
 * </pre>
 * <p>
 * The behavior of the <code>add</code> and
 * <code>setLayout</code> methods for
 * <code>JFrame</code>, <code>JDialog</code>, <code>JWindow</code>,
 * <code>JApplet</code> and <code>JInternalFrame</code> is controlled by
 * the <code>rootPaneCheckingEnabled</code> property. If this property is
 * true (the default), then calls to these methods are
  * forwarded to the <code>contentPane</code>; if false, these
  * methods operate directly on the <code>RootPaneContainer</code>. This
  * property is only intended for subclasses, and is therefore protected.
 *
 * @see JRootPane
 * @see JFrame
 * @see JDialog
 * @see JWindow
 * @see JApplet
 * @see JInternalFrame
 *
 * @author Hans Muller
 */
public interface RootPaneContainer
{
    
Return this component's single JRootPane child.  A conventional
implementation of this interface will have all of the other
methods indirect through this one.  The rootPane has two
children: the glassPane and the layeredPane.

See Also:
Returns:this components single JRootPane child.
/**
     * Return this component's single JRootPane child.  A conventional
     * implementation of this interface will have all of the other
     * methods indirect through this one.  The rootPane has two
     * children: the glassPane and the layeredPane.
     *
     * @return this components single JRootPane child.
     * @see JRootPane
     */
    JRootPane getRootPane();


    
The "contentPane" is the primary container for application
specific components.  Applications should add children to
the contentPane, set its layout manager, and so on.


The contentPane may not be null.


Generally implemented with
getRootPane().setContentPane(contentPane);

Params:
  • contentPane – the Container to use for the contents of this
       JRootPane
Throws:
  • IllegalComponentStateException – (a runtime
           exception) if the content pane parameter is null
See Also:
/**
     * The "contentPane" is the primary container for application
     * specific components.  Applications should add children to
     * the contentPane, set its layout manager, and so on.
     * <p>
     * The contentPane may not be null.
     * <p>
     * Generally implemented with
     * <code>getRootPane().setContentPane(contentPane);</code>
     *
     * @exception java.awt.IllegalComponentStateException (a runtime
     *            exception) if the content pane parameter is null
     * @param contentPane the Container to use for the contents of this
     *        JRootPane
     * @see JRootPane#getContentPane
     * @see #getContentPane
     */
    void setContentPane(Container contentPane);


    
Returns the contentPane.

See Also:
Returns:the value of the contentPane property.
/**
     * Returns the contentPane.
     *
     * @return the value of the contentPane property.
     * @see #setContentPane
     */
    Container getContentPane();


    
A Container that manages the contentPane and in some cases a menu bar.
The layeredPane can be used by descendants that want to add a child
to the RootPaneContainer that isn't layout managed.  For example
an internal dialog or a drag and drop effect component.


The layeredPane may not be null.


Generally implemented with
   getRootPane().setLayeredPane(layeredPane);


Throws:
  • IllegalComponentStateException – (a runtime
           exception) if the layered pane parameter is null
See Also:
/**
     * A Container that manages the contentPane and in some cases a menu bar.
     * The layeredPane can be used by descendants that want to add a child
     * to the RootPaneContainer that isn't layout managed.  For example
     * an internal dialog or a drag and drop effect component.
     * <p>
     * The layeredPane may not be null.
     * <p>
     * Generally implemented with<pre>
     *    getRootPane().setLayeredPane(layeredPane);</pre>
     *
     * @exception java.awt.IllegalComponentStateException (a runtime
     *            exception) if the layered pane parameter is null
     * @see #getLayeredPane
     * @see JRootPane#getLayeredPane
     */
    void setLayeredPane(JLayeredPane layeredPane);


    
Returns the layeredPane.

See Also:
Returns:the value of the layeredPane property.
/**
     * Returns the layeredPane.
     *
     * @return the value of the layeredPane property.
     * @see #setLayeredPane
     */
    JLayeredPane getLayeredPane();


    
The glassPane is always the first child of the rootPane
and the rootPanes layout manager ensures that it's always
as big as the rootPane.  By default it's transparent and
not visible.  It can be used to temporarily grab all keyboard
and mouse input by adding listeners and then making it visible.
by default it's not visible.


The glassPane may not be null.


Generally implemented with
getRootPane().setGlassPane(glassPane);

See Also:
/**
     * The glassPane is always the first child of the rootPane
     * and the rootPanes layout manager ensures that it's always
     * as big as the rootPane.  By default it's transparent and
     * not visible.  It can be used to temporarily grab all keyboard
     * and mouse input by adding listeners and then making it visible.
     * by default it's not visible.
     * <p>
     * The glassPane may not be null.
     * <p>
     * Generally implemented with
     * <code>getRootPane().setGlassPane(glassPane);</code>
     *
     * @see #getGlassPane
     * @see JRootPane#setGlassPane
     */
    void setGlassPane(Component glassPane);


    
Returns the glassPane.

See Also:
Returns:the value of the glassPane property.
/**
     * Returns the glassPane.
     *
     * @return the value of the glassPane property.
     * @see #setGlassPane
     */
    Component getGlassPane();

}