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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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*/
package java.awt;
/**
* The <code>CheckboxGroup</code> class is used to group together
* a set of <code>Checkbox</code> buttons.
* <p>
* Exactly one check box button in a <code>CheckboxGroup</code> can
* be in the "on" state at any given time. Pushing any
* button sets its state to "on" and forces any other button that
* is in the "on" state into the "off" state.
* <p>
* The following code example produces a new check box group,
* with three check boxes:
* <p>
* <hr><blockquote><pre>
* setLayout(new GridLayout(3, 1));
* CheckboxGroup cbg = new CheckboxGroup();
* add(new Checkbox("one", cbg, true));
* add(new Checkbox("two", cbg, false));
* add(new Checkbox("three", cbg, false));
* </pre></blockquote><hr>
* <p>
* This image depicts the check box group created by this example:
* <p>
* <img src="doc-files/CheckboxGroup-1.gif"
* alt="Shows three checkboxes, arranged vertically, labeled one, two, and three. Checkbox one is in the on state."
* ALIGN=center HSPACE=10 VSPACE=7>
* <p>
* @author Sami Shaio
* @see java.awt.Checkbox
* @since JDK1.0
*/
public class CheckboxGroup implements java.io.Serializable {
/**
* The current choice.
* @serial
* @see #getCurrent()
* @see #setCurrent(Checkbox)
*/
Checkbox selectedCheckbox = null;
/*
* JDK 1.1 serialVersionUID
*/
private static final long serialVersionUID = 3729780091441768983L;
/**
* Creates a new instance of <code>CheckboxGroup</code>.
*/
public CheckboxGroup() {
}
/**
* Gets the current choice from this check box group.
* The current choice is the check box in this
* group that is currently in the "on" state,
* or <code>null</code> if all check boxes in the
* group are off.
* @return the check box that is currently in the
* "on" state, or <code>null</code>.
* @see java.awt.Checkbox
* @see java.awt.CheckboxGroup#setSelectedCheckbox
* @since JDK1.1
*/
public Checkbox getSelectedCheckbox() {
return getCurrent();
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getSelectedCheckbox()</code>.
*/
@Deprecated
public Checkbox getCurrent() {
return selectedCheckbox;
}
/**
* Sets the currently selected check box in this group
* to be the specified check box.
* This method sets the state of that check box to "on" and
* sets all other check boxes in the group to be off.
* <p>
* If the check box argument is <tt>null</tt>, all check boxes
* in this check box group are deselected. If the check box argument
* belongs to a different check box group, this method does
* nothing.
* @param box the <code>Checkbox</code> to set as the
* current selection.
* @see java.awt.Checkbox
* @see java.awt.CheckboxGroup#getSelectedCheckbox
* @since JDK1.1
*/
public void setSelectedCheckbox(Checkbox box) {
setCurrent(box);
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>setSelectedCheckbox(Checkbox)</code>.
*/
@Deprecated
public synchronized void setCurrent(Checkbox box) {
if (box != null && box.group != this) {
return;
}
Checkbox oldChoice = this.selectedCheckbox;
this.selectedCheckbox = box;
if (oldChoice != null && oldChoice != box && oldChoice.group == this) {
oldChoice.setState(false);
}
if (box != null && oldChoice != box && !box.getState()) {
box.setStateInternal(true);
}
}
/**
* Returns a string representation of this check box group,
* including the value of its current selection.
* @return a string representation of this check box group.
*/
public String toString() {
return getClass().getName() + "[selectedCheckbox=" + selectedCheckbox + "]";
}
}