AccessibleTitledPanel.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.framework.uitools;

import java.awt.Container;
import java.awt.LayoutManager;
import javax.accessibility.AccessibleContext;
import javax.swing.JComponent;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTabbedPane;
import javax.swing.border.Border;
import javax.swing.border.CompoundBorder;
import javax.swing.border.TitledBorder;

/**
 * This panel is meant to traverse more than just the direct parent in order
 * to retrieve the accessible name, which is usually the title of a
 * <code>GroupBox</code>. Typically, this panel should be used inside of a
 * <code>GroupBox</code> only, otherwise a <code>JPanel</code> should be used.
 */
public class AccessibleTitledPanel
    extends JPanel
{

    public AccessibleTitledPanel() {
        super();
    }

    public AccessibleTitledPanel(LayoutManager layoutManager) {
        super(layoutManager);
    }

    public AccessibleContext getAccessibleContext() {
        if (this.accessibleContext == null) {
            this.accessibleContext = new AccessibleAccessibleTitledPane();
        }
        return this.accessibleContext;
    }


    // ********** member class **********

    /**
     * The <code>AccessibleContext</code> for <code>AccessibleTitledPanel</code>.
     */
    protected class AccessibleAccessibleTitledPane
        extends AccessibleJPanel
    {
        /**
         * Return whether the container is a <code>JComponent</code>
         * that might have a titled border.
         */
        private boolean containerIsValid(Container container) {
            return (container instanceof JComponent) &&
                     ! (container instanceof JScrollPane) &&
                    ! (container instanceof JSplitPane) &&
                    ! (container instanceof JTabbedPane);
        }

        /**
         * Recursively search through the border hierarchy (if it exists) for a
         * TitledBorder with a non-null title. This does a depth first search on
         * first the inside borders then the outside borders. The assumption is
         * that titles make really pretty inside borders but not very pretty
         * outside borders in compound border situations. It's rather arbitrary,
         * but hopefully decent UI programmers will not create multiple titled
         * borders for the same component.
         */
        private String findTitle(Border border) {
            if (border instanceof TitledBorder) {
                return ((TitledBorder) border).getTitle();
            }

            if (border instanceof CompoundBorder) {
                CompoundBorder compoundBorder = (CompoundBorder) border;
                String title = this.findTitle(compoundBorder.getInsideBorder());

                if (title == null) {
                    title = this.findTitle(compoundBorder.getOutsideBorder());
                }
                return title;
            }
            return null;
        }

        /**
         * Return the titled border text.
         */
        public String getTitledBorderText() {
            return traverseForTitleText(AccessibleTitledPanel.this);
        }

        /**
         * Checks to see if the given container has a titled border as its border
         * and to see if it has a title.
         */
        private String traverseForTitleText(Container container) {
            if (this.containerIsValid(container)) {
                JComponent jComponent = (JComponent) container;
                String title = this.findTitle(jComponent.getBorder());

                if (title != null) {
                    return title;
                }
                return this.traverseForTitleText(jComponent.getParent());
            }
            return null;
        }

        /**
         * Recursively search through the border hierarchy (if it exists) and also
         * through the parent hierarchy for a <code>TitledBorder</code> with a
         * non-<code>null</code> title. This does a depth first search on first
         * the inside borders then the outside borders. The assumption is that
         * titles make really pretty inside borders but not very pretty outside
         * borders in compound border situations. It's rather arbitrary.
         */
        protected String getBorderTitle(Border border) {
            return this.getTitledBorderText();
        }

    }

}