| /* | |
| * Copyright (c) 1999, 2025, 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; | |
| import java.io.Serial; | |
| /** | |
| * An event which indicates a change to the {@code Component} | |
| * hierarchy to which {@code Component} 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 removeNotify}, {@code show}, or | |
| * {@code hide} method is called. The {@code ANCESTOR_MOVED} and | |
| * {@code ANCESTOR_RESIZED} | |
| * events are dispatched to every {@code HierarchyBoundsListener} or | |
| * {@code HierarchyBoundsAdapter} object which registered to receive | |
| * such events using the Component's {@code addHierarchyBoundsListener} | |
| * method. ({@code HierarchyBoundsAdapter} objects implement the | |
| * {@code HierarchyBoundsListener} interface.) The {@code HIERARCHY_CHANGED} events are | |
| * dispatched to every {@code HierarchyListener} object which registered | |
| * to receive such events using the Component's {@code addHierarchyListener} | |
| * method. Each such listener object gets this {@code HierarchyEvent} | |
| * 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 { | |
| /** | |
| * Use serialVersionUID from JDK 1.6 for interoperability. | |
| */ | |
| @Serial | |
| 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} event | |
| * was generated by a reparenting operation. | |
| */ | |
| public static final int PARENT_CHANGED = 0x1; | |
| /** | |
| * A change flag indicates that the {@code HIERARCHY_CHANGED} event | |
| * was generated due to the changing of the hierarchy displayability. | |
| * To discern the | |
| * current displayability of the hierarchy, call the | |
| * {@code Component.isDisplayable} method. Displayability changes occur | |
| * in response to explicit or implicit calls of the | |
| * {@code Component.addNotify} and | |
| * {@code Component.removeNotify} 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} 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} 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} and | |
| * {@code Component.hide} 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; | |
| /** | |
| * @serial The {@code Component} at the top of the hierarchy which was changed. | |
| */ | |
| Component changed; | |
| /** | |
| * @serial The parent of the {@code changed} component. This may be the parent | |
| * before or after the change, depending on the type of change. | |
| */ | |
| Container changedParent; | |
| /** | |
| * @serial A bitmask which indicates the type(s) of the {@code HIERARCHY_CHANGED} | |
| * events represented in this event object. For information on allowable | |
| * values, see the class description for {@link HierarchyEvent} | |
| */ | |
| long changeFlags; | |
| /** | |
| * Constructs an {@code HierarchyEvent} object to identify a | |
| * change in the {@code Component} hierarchy. | |
| * <p>This method throws an | |
| * {@code IllegalArgumentException} if {@code source} | |
| * is {@code null}. | |
| * | |
| * @param source The {@code Component} 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} at the top of | |
| * the hierarchy which was changed | |
| * @param changedParent The parent of the {@code changed} component. | |
| * This | |
| * may be the parent before or after the | |
| * change, depending on the type of change | |
| * @throws IllegalArgumentException if {@code source} 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} object to identify | |
| * a change in the {@code Component} hierarchy. | |
| * <p> This method throws an | |
| * {@code IllegalArgumentException} if {@code source} | |
| * is {@code null}. | |
| * | |
| * @param source The {@code Component} 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} at the top | |
| * of the hierarchy which was changed | |
| * @param changedParent The parent of the {@code changed} 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} events | |
| * represented in this event object. | |
| * For information on allowable values, see | |
| * the class description for {@link HierarchyEvent} | |
| * @throws IllegalArgumentException if {@code source} 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} object that originated | |
| * the event, or {@code null} if the object is not a | |
| * {@code Component}. | |
| */ | |
| 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()}. For a HIERARCHY_CHANGED event where the | |
| * change was of type PARENT_CHANGED via a call to | |
| * {@code Container.add}, 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}, 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; | |
| } | |
| } |