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package javax.swing;


import java.awt.Component;
import java.awt.FocusTraversalPolicy;


A FocusTraversalPolicy which can optionally provide an algorithm for
determining a JInternalFrame's initial Component. The initial Component is
the first to receive focus when the JInternalFrame is first selected. By
default, this is the same as the JInternalFrame's default Component to
focus.

Author:David Mendenhall
Since:1.4
/**
 * A FocusTraversalPolicy which can optionally provide an algorithm for
 * determining a JInternalFrame's initial Component. The initial Component is
 * the first to receive focus when the JInternalFrame is first selected. By
 * default, this is the same as the JInternalFrame's default Component to
 * focus.
 *
 * @author David Mendenhall
 *
 * @since 1.4
 */
public abstract class InternalFrameFocusTraversalPolicy
    extends FocusTraversalPolicy
{

    
Returns the Component that should receive the focus when a
JInternalFrame is selected for the first time. Once the JInternalFrame
has been selected by a call to setSelected(true), the
initial Component will not be used again. Instead, if the JInternalFrame
loses and subsequently regains selection, or is made invisible or
undisplayable and subsequently made visible and displayable, the
JInternalFrame's most recently focused Component will become the focus
owner. The default implementation of this method returns the
JInternalFrame's default Component to focus.

Params:
  • frame – the JInternalFrame whose initial Component is to be
       returned
Throws:
See Also:
Returns:the Component that should receive the focus when frame is
        selected for the first time, or null if no suitable Component
        can be found
/**
     * Returns the Component that should receive the focus when a
     * JInternalFrame is selected for the first time. Once the JInternalFrame
     * has been selected by a call to <code>setSelected(true)</code>, the
     * initial Component will not be used again. Instead, if the JInternalFrame
     * loses and subsequently regains selection, or is made invisible or
     * undisplayable and subsequently made visible and displayable, the
     * JInternalFrame's most recently focused Component will become the focus
     * owner. The default implementation of this method returns the
     * JInternalFrame's default Component to focus.
     *
     * @param frame the JInternalFrame whose initial Component is to be
     *        returned
     * @return the Component that should receive the focus when frame is
     *         selected for the first time, or null if no suitable Component
     *         can be found
     * @see JInternalFrame#getMostRecentFocusOwner
     * @throws IllegalArgumentException if window is null
     */
    public Component getInitialComponent(JInternalFrame frame) {
        return getDefaultComponent(frame);
    }
}