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	/*
	* Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.awt.event;

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

	/**
	* An event which indicates a change to the <code>Component</code>
	* hierarchy to which <code>Component</code> belongs.
	* <ul>
	* <li>Hierarchy Change Events (HierarchyListener)
	* <ul>
	* <li> addition of an ancestor
	* <li> removal of an ancestor
	* <li> hierarchy made displayable
	* <li> hierarchy made undisplayable
	* <li> hierarchy shown on the screen (both visible and displayable)
	* <li> hierarchy hidden on the screen (either invisible or undisplayable)
	* </ul>
	* <li>Ancestor Reshape Events (HierarchyBoundsListener)
	* <ul>
	* <li> an ancestor was resized
	* <li> an ancestor was moved
	* </ul>
	* </ul>
	* <p>
	* Hierarchy events are provided for notification purposes ONLY.
	* The AWT will automatically handle changes to the hierarchy internally so
	* that GUI layout and displayability works properly regardless of whether a
	* program is receiving these events or not.
	* <p>
	* This event is generated by a Container object (such as a Panel) when the
	* Container is added, removed, moved, or resized, and passed down the
	* hierarchy. It is also generated by a Component object when that object's
	* <code>addNotify</code>, <code>removeNotify</code>, <code>show</code>, or
	* <code>hide</code> method is called. The {@code ANCESTOR_MOVED} and
	* {@code ANCESTOR_RESIZED}
	* events are dispatched to every <code>HierarchyBoundsListener</code> or
	* <code>HierarchyBoundsAdapter</code> object which registered to receive
	* such events using the Component's <code>addHierarchyBoundsListener</code>
	* method. (<code>HierarchyBoundsAdapter</code> objects implement the <code>
	* HierarchyBoundsListener</code> interface.) The {@code HIERARCHY_CHANGED} events are
	* dispatched to every <code>HierarchyListener</code> object which registered
	* to receive such events using the Component's <code>addHierarchyListener
	* </code> method. Each such listener object gets this <code>HierarchyEvent
	* </code> when the event occurs.
	* <p>
	* An unspecified behavior will be caused if the {@code id} parameter
	* of any particular {@code HierarchyEvent} instance is not
	* in the range from {@code HIERARCHY_FIRST} to {@code HIERARCHY_LAST}.
	* <br>
	* The {@code changeFlags} parameter of any {@code HierarchyEvent} instance takes one of the following
	* values:
	* <ul>
	* <li> {@code HierarchyEvent.PARENT_CHANGED}
	* <li> {@code HierarchyEvent.DISPLAYABILITY_CHANGED}
	* <li> {@code HierarchyEvent.SHOWING_CHANGED}
	* </ul>
	* Assigning the value different from listed above will cause unspecified behavior.
	*
	* @author David Mendenhall
	* @see HierarchyListener
	* @see HierarchyBoundsAdapter
	* @see HierarchyBoundsListener
	* @since 1.3
	*/
	public class HierarchyEvent extends AWTEvent {
	/*
	* serialVersionUID
	*/
	private static final long serialVersionUID = -5337576970038043990L;

	/**
	* Marks the first integer id for the range of hierarchy event ids.
	*/
	public static final int HIERARCHY_FIRST = 1400; // 1300 used by sun.awt.windows.ModalityEvent

	/**
	* The event id indicating that modification was made to the
	* entire hierarchy tree.
	*/
	public static final int HIERARCHY_CHANGED = HIERARCHY_FIRST;

	/**
	* The event id indicating an ancestor-Container was moved.
	*/
	public static final int ANCESTOR_MOVED = 1 + HIERARCHY_FIRST;

	/**
	* The event id indicating an ancestor-Container was resized.
	*/
	public static final int ANCESTOR_RESIZED = 2 + HIERARCHY_FIRST;

	/**
	* Marks the last integer id for the range of ancestor event ids.
	*/
	public static final int HIERARCHY_LAST = ANCESTOR_RESIZED;

	/**
	* A change flag indicates that the <code>HIERARCHY_CHANGED</code> event
	* was generated by a reparenting operation.
	*/
	public static final int PARENT_CHANGED = 0x1;

	/**
	* A change flag indicates that the <code>HIERARCHY_CHANGED</code> event
	* was generated due to the changing of the hierarchy displayability.
	* To discern the
	* current displayability of the hierarchy, call the
	* <code>Component.isDisplayable</code> method. Displayability changes occur
	* in response to explicit or implicit calls of the
	* <code>Component.addNotify</code> and
	* <code>Component.removeNotify</code> methods.
	*
	* @see java.awt.Component#isDisplayable()
	* @see java.awt.Component#addNotify()
	* @see java.awt.Component#removeNotify()
	*/
	public static final int DISPLAYABILITY_CHANGED = 0x2;

	/**
	* A change flag indicates that the <code>HIERARCHY_CHANGED</code> event
	* was generated due to the changing of the hierarchy showing state.
	* To discern the
	* current showing state of the hierarchy, call the
	* <code>Component.isShowing</code> method. Showing state changes occur
	* when either the displayability or visibility of the
	* hierarchy occurs. Visibility changes occur in response to explicit
	* or implicit calls of the <code>Component.show</code> and
	* <code>Component.hide</code> methods.
	*
	* @see java.awt.Component#isShowing()
	* @see java.awt.Component#addNotify()
	* @see java.awt.Component#removeNotify()
	* @see java.awt.Component#show()
	* @see java.awt.Component#hide()
	*/
	public static final int SHOWING_CHANGED = 0x4;

	Component changed;
	Container changedParent;
	long changeFlags;

	/**
	* Constructs an <code>HierarchyEvent</code> object to identify a
	* change in the <code>Component</code> hierarchy.
	* <p>This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	*
	* @param source The <code>Component</code> object that
	* originated the event
	* @param id An integer indicating the type of event.
	* For information on allowable values, see
	* the class description for {@link HierarchyEvent}
	* @param changed The <code>Component</code> at the top of
	* the hierarchy which was changed
	* @param changedParent The parent of the <code>changed</code> component.
	* This
	* may be the parent before or after the
	* change, depending on the type of change
	* @throws IllegalArgumentException if <code>source</code> is {@code null}
	* @see #getSource()
	* @see #getID()
	* @see #getChanged()
	* @see #getChangedParent()
	*/
	public HierarchyEvent(Component source, int id, Component changed,
	Container changedParent) {
	super(source, id);
	this.changed = changed;
	this.changedParent = changedParent;
	}

	/**
	* Constructs an <code>HierarchyEvent</code> object to identify
	* a change in the <code>Component</code> hierarchy.
	* <p> This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	*
	* @param source The <code>Component</code> object that
	* originated the event
	* @param id An integer indicating the type of event.
	* For information on allowable values, see
	* the class description for {@link HierarchyEvent}
	* @param changed The <code>Component</code> at the top
	* of the hierarchy which was changed
	* @param changedParent The parent of the <code>changed</code> component.
	* This
	* may be the parent before or after the
	* change, depending on the type of change
	* @param changeFlags A bitmask which indicates the type(s) of
	* the <code>HIERARCHY_CHANGED</code> events
	* represented in this event object.
	* For information on allowable values, see
	* the class description for {@link HierarchyEvent}
	* @throws IllegalArgumentException if <code>source</code> is null
	* @see #getSource()
	* @see #getID()
	* @see #getChanged()
	* @see #getChangedParent()
	* @see #getChangeFlags()
	*/
	public HierarchyEvent(Component source, int id, Component changed,
	Container changedParent, long changeFlags) {
	super(source, id);
	this.changed = changed;
	this.changedParent = changedParent;
	this.changeFlags = changeFlags;
	}

	/**
	* Returns the originator of the event.
	*
	* @return the <code>Component</code> object that originated
	* the event, or <code>null</code> if the object is not a
	* <code>Component</code>.
	*/
	public Component getComponent() {
	return (source instanceof Component) ? (Component)source : null;
	}

	/**
	* Returns the Component at the top of the hierarchy which was
	* changed.
	*
	* @return the changed Component
	*/
	public Component getChanged() {
	return changed;
	}

	/**
	* Returns the parent of the Component returned by <code>
	* getChanged()</code>. For a HIERARCHY_CHANGED event where the
	* change was of type PARENT_CHANGED via a call to <code>
	* Container.add</code>, the parent returned is the parent
	* after the add operation. For a HIERARCHY_CHANGED event where
	* the change was of type PARENT_CHANGED via a call to <code>
	* Container.remove</code>, the parent returned is the parent
	* before the remove operation. For all other events and types,
	* the parent returned is the parent during the operation.
	*
	* @return the parent of the changed Component
	*/
	public Container getChangedParent() {
	return changedParent;
	}

	/**
	* Returns a bitmask which indicates the type(s) of
	* HIERARCHY_CHANGED events represented in this event object.
	* The bits have been bitwise-ored together.
	*
	* @return the bitmask, or 0 if this is not an HIERARCHY_CHANGED
	* event
	*/
	public long getChangeFlags() {
	return changeFlags;
	}

	/**
	* Returns a parameter string identifying this event.
	* This method is useful for event-logging and for debugging.
	*
	* @return a string identifying the event and its attributes
	*/
	public String paramString() {
	String typeStr;
	switch(id) {
	case ANCESTOR_MOVED:
	typeStr = "ANCESTOR_MOVED ("+changed+","+changedParent+")";
	break;
	case ANCESTOR_RESIZED:
	typeStr = "ANCESTOR_RESIZED ("+changed+","+changedParent+")";
	break;
	case HIERARCHY_CHANGED: {
	typeStr = "HIERARCHY_CHANGED (";
	boolean first = true;
	if ((changeFlags & PARENT_CHANGED) != 0) {
	first = false;
	typeStr += "PARENT_CHANGED";
	}
	if ((changeFlags & DISPLAYABILITY_CHANGED) != 0) {
	if (first) {
	first = false;
	} else {
	typeStr += ",";
	}
	typeStr += "DISPLAYABILITY_CHANGED";
	}
	if ((changeFlags & SHOWING_CHANGED) != 0) {
	if (first) {
	first = false;
	} else {
	typeStr += ",";
	}
	typeStr += "SHOWING_CHANGED";
	}
	if (!first) {
	typeStr += ",";
	}
	typeStr += changed + "," + changedParent + ")";
	break;
	}
	default:
	typeStr = "unknown type";
	}
	return typeStr;
	}
	}

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