--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.desktop/share/classes/javax/swing/ButtonGroup.java Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,194 @@
+/*
+ * Copyright (c) 1997, 2013, 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 javax.swing;
+
+import java.awt.event.*;
+import java.util.Vector;
+import java.util.Enumeration;
+import java.io.Serializable;
+
+/**
+ * This class is used to create a multiple-exclusion scope for
+ * a set of buttons. Creating a set of buttons with the
+ * same <code>ButtonGroup</code> object means that
+ * turning "on" one of those buttons
+ * turns off all other buttons in the group.
+ * <p>
+ * A <code>ButtonGroup</code> can be used with
+ * any set of objects that inherit from <code>AbstractButton</code>.
+ * Typically a button group contains instances of
+ * <code>JRadioButton</code>,
+ * <code>JRadioButtonMenuItem</code>,
+ * or <code>JToggleButton</code>.
+ * It wouldn't make sense to put an instance of
+ * <code>JButton</code> or <code>JMenuItem</code>
+ * in a button group
+ * because <code>JButton</code> and <code>JMenuItem</code>
+ * don't implement the selected state.
+ * <p>
+ * Initially, all buttons in the group are unselected.
+ * <p>
+ * For examples and further information on using button groups see
+ * <a href="http://docs.oracle.com/javase/tutorial/uiswing/components/button.html#radiobutton">How to Use Radio Buttons</a>,
+ * a section in <em>The Java Tutorial</em>.
+ * <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 Jeff Dinkins
+ * @since 1.2
+ */
+@SuppressWarnings("serial")
+public class ButtonGroup implements Serializable {
+
+ // the list of buttons participating in this group
+ protected Vector<AbstractButton> buttons = new Vector<AbstractButton>();
+
+ /**
+ * The current selection.
+ */
+ ButtonModel selection = null;
+
+ /**
+ * Creates a new <code>ButtonGroup</code>.
+ */
+ public ButtonGroup() {}
+
+ /**
+ * Adds the button to the group.
+ * @param b the button to be added
+ */
+ public void add(AbstractButton b) {
+ if(b == null) {
+ return;
+ }
+ buttons.addElement(b);
+
+ if (b.isSelected()) {
+ if (selection == null) {
+ selection = b.getModel();
+ } else {
+ b.setSelected(false);
+ }
+ }
+
+ b.getModel().setGroup(this);
+ }
+
+ /**
+ * Removes the button from the group.
+ * @param b the button to be removed
+ */
+ public void remove(AbstractButton b) {
+ if(b == null) {
+ return;
+ }
+ buttons.removeElement(b);
+ if(b.getModel() == selection) {
+ selection = null;
+ }
+ b.getModel().setGroup(null);
+ }
+
+ /**
+ * Clears the selection such that none of the buttons
+ * in the <code>ButtonGroup</code> are selected.
+ *
+ * @since 1.6
+ */
+ public void clearSelection() {
+ if (selection != null) {
+ ButtonModel oldSelection = selection;
+ selection = null;
+ oldSelection.setSelected(false);
+ }
+ }
+
+ /**
+ * Returns all the buttons that are participating in
+ * this group.
+ * @return an <code>Enumeration</code> of the buttons in this group
+ */
+ public Enumeration<AbstractButton> getElements() {
+ return buttons.elements();
+ }
+
+ /**
+ * Returns the model of the selected button.
+ * @return the selected button model
+ */
+ public ButtonModel getSelection() {
+ return selection;
+ }
+
+ /**
+ * Sets the selected value for the <code>ButtonModel</code>.
+ * Only one button in the group may be selected at a time.
+ * @param m the <code>ButtonModel</code>
+ * @param b <code>true</code> if this button is to be
+ * selected, otherwise <code>false</code>
+ */
+ public void setSelected(ButtonModel m, boolean b) {
+ if (b && m != null && m != selection) {
+ ButtonModel oldSelection = selection;
+ selection = m;
+ if (oldSelection != null) {
+ oldSelection.setSelected(false);
+ }
+ m.setSelected(true);
+ }
+ }
+
+ /**
+ * Returns whether a {@code ButtonModel} is selected.
+ *
+ * @param m an isntance of {@code ButtonModel}
+ * @return {@code true} if the button is selected,
+ * otherwise returns {@code false}
+ */
+ public boolean isSelected(ButtonModel m) {
+ return (m == selection);
+ }
+
+ /**
+ * Returns the number of buttons in the group.
+ * @return the button count
+ * @since 1.3
+ */
+ public int getButtonCount() {
+ if (buttons == null) {
+ return 0;
+ } else {
+ return buttons.size();
+ }
+ }
+
+}