JSeparator.java

/*
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 * 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
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packagejavax.swing;

importjava.beans.BeanProperty;
importjava.beans.JavaBean;
importjava.io.IOException;
importjava.io.ObjectOutputStream;
importjava.io.Serial;

importjavax.accessibility.Accessible;
importjavax.accessibility.AccessibleContext;
importjavax.accessibility.AccessibleRole;
importjavax.swing.plaf.SeparatorUI;

/**
 * <code>JSeparator</code> provides a general purpose component for
 * implementing divider lines - most commonly used as a divider
 * between menu items that breaks them up into logical groupings.
 * Instead of using <code>JSeparator</code> directly,
 * you can use the <code>JMenu</code> or <code>JPopupMenu</code>
 * <code>addSeparator</code> method to create and add a separator.
 * <code>JSeparator</code>s may also be used elsewhere in a GUI
 * wherever a visual divider is useful.
 *
 * <p>
 *
 * For more information and examples see
 * <a
 href="https://docs.oracle.com/javase/tutorial/uiswing/components/menu.html">How to Use Menus</a>,
 * a section in <em>The Java Tutorial.</em>
 * <p>
 * <strong>Warning:</strong> Swing is not thread safe. For more
 * information see <a
 * href="package-summary.html#threading">Swing's Threading
 * Policy</a>.
 * <p>
 * <strong>Warning:</strong>
 * 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. As of 1.4, support for long term storage
 * of all JavaBeans
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Georges Saab
 * @author Jeff Shapiro
 * @since 1.2
 */
@JavaBean(defaultProperty = "UI", description = "A divider between menu items.")
@SwingContainer(false)
@SuppressWarnings("serial")
publicclassJSeparatorextendsJComponentimplementsSwingConstants, Accessible
{
/**
 * @see #getUIClassID
 * @see #readObject
 */
privatestaticfinalStringuiClassID = "SeparatorUI";

privateintorientation = HORIZONTAL;

/** Creates a new horizontal separator. */
publicJSeparator()
 {
this( HORIZONTAL );
 }

/**
 * Creates a new separator with the specified horizontal or
 * vertical orientation.
 *
 * @param orientation an integer specifying
 * <code>SwingConstants.HORIZONTAL</code> or
 * <code>SwingConstants.VERTICAL</code>
 * @throws IllegalArgumentException if <code>orientation</code>
 * is neither <code>SwingConstants.HORIZONTAL</code> nor
 * <code>SwingConstants.VERTICAL</code>
 */
publicJSeparator( intorientation )
 {
checkOrientation( orientation );
this.orientation = orientation;
setFocusable(false);
updateUI();
 }

/**
 * Returns the L&amp;F object that renders this component.
 *
 * @return the SeparatorUI object that renders this component
 */
publicSeparatorUIgetUI() {
return (SeparatorUI)ui;
 }

/**
 * Sets the L&amp;F object that renders this component.
 *
 * @param ui the SeparatorUI L&amp;F object
 * @see UIDefaults#getUI
 */
@BeanProperty(hidden = true, visualUpdate = true, description
 = "The UI object that implements the Component's LookAndFeel.")
publicvoidsetUI(SeparatorUIui) {
super.setUI(ui);
 }

/**
 * Resets the UI property to a value from the current look and feel.
 *
 * @see JComponent#updateUI
 */
publicvoidupdateUI() {
setUI((SeparatorUI)UIManager.getUI(this));
 }


/**
 * Returns the name of the L&amp;F class that renders this component.
 *
 * @return the string "SeparatorUI"
 * @see JComponent#getUIClassID
 * @see UIDefaults#getUI
 */
@BeanProperty(bound = false)
publicStringgetUIClassID() {
returnuiClassID;
 }


/**
 * See <code>readObject</code> and <code>writeObject</code> in
 * <code>JComponent</code> for more
 * information about serialization in Swing.
 */
@Serial
privatevoidwriteObject(ObjectOutputStreams) throwsIOException {
s.defaultWriteObject();
if (getUIClassID().equals(uiClassID)) {
bytecount = JComponent.getWriteObjCounter(this);
JComponent.setWriteObjCounter(this, --count);
if (count == 0 && ui != null) {
ui.installUI(this);
 }
 }
 }

/**
 * Returns the orientation of this separator.
 *
 * @return The value of the orientation property, one of the
 * following constants defined in <code>SwingConstants</code>:
 * <code>VERTICAL</code>, or
 * <code>HORIZONTAL</code>.
 *
 * @see SwingConstants
 * @see #setOrientation
 */
publicintgetOrientation() {
returnthis.orientation;
 }

/**
 * Sets the orientation of the separator.
 * The default value of this property is HORIZONTAL.
 * @param orientation either <code>SwingConstants.HORIZONTAL</code>
 * or <code>SwingConstants.VERTICAL</code>
 * @throws IllegalArgumentException if <code>orientation</code>
 * is neither <code>SwingConstants.HORIZONTAL</code>
 * nor <code>SwingConstants.VERTICAL</code>
 *
 * @see SwingConstants
 * @see #getOrientation
 */
@BeanProperty(preferred = true, visualUpdate = true, enumerationValues = {
"SwingConstants.HORIZONTAL",
"SwingConstants.VERTICAL"}, description
 = "The orientation of the separator.")
publicvoidsetOrientation( intorientation ) {
if (this.orientation == orientation) {
return;
 }
intoldValue = this.orientation;
checkOrientation( orientation );
this.orientation = orientation;
firePropertyChange("orientation", oldValue, orientation);
revalidate();
repaint();
 }

privatevoidcheckOrientation( intorientation )
 {
switch ( orientation )
 {
caseVERTICAL:
caseHORIZONTAL:
break;
default:
thrownewIllegalArgumentException( "orientation must be one of: VERTICAL, HORIZONTAL" );
 }
 }


/**
 * Returns a string representation of this <code>JSeparator</code>.
 * 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 <code>null</code>.
 *
 * @return a string representation of this <code>JSeparator</code>
 */
protectedStringparamString() {
StringorientationString = (orientation == HORIZONTAL ?
"HORIZONTAL" : "VERTICAL");

returnsuper.paramString() +
",orientation=" + orientationString;
 }

/////////////////
// Accessibility support
////////////////

/**
 * Gets the AccessibleContext associated with this JSeparator.
 * For separators, the AccessibleContext takes the form of an
 * AccessibleJSeparator.
 * A new AccessibleJSeparator instance is created if necessary.
 *
 * @return an AccessibleJSeparator that serves as the
 * AccessibleContext of this JSeparator
 */
@BeanProperty(bound = false)
publicAccessibleContextgetAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = newAccessibleJSeparator();
 }
returnaccessibleContext;
 }

/**
 * This class implements accessibility support for the
 * <code>JSeparator</code> class. It provides an implementation of the
 * Java Accessibility API appropriate to separator user-interface elements.
 * <p>
 * <strong>Warning:</strong>
 * 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. As of 1.4, support for long term storage
 * of all JavaBeans
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 */
@SuppressWarnings("serial")
protectedclassAccessibleJSeparatorextendsAccessibleJComponent {

/**
 * Constructs an {@code AccessibleJSeparator}.
 */
protectedAccessibleJSeparator() {}

/**
 * Get the role of this object.
 *
 * @return an instance of AccessibleRole describing the role of the
 * object
 */
publicAccessibleRolegetAccessibleRole() {
returnAccessibleRole.SEPARATOR;
 }
 }
}