AbstractPreferencesNode.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.app;

import java.awt.Component;
import java.util.prefs.Preferences;

import javax.swing.Icon;
import javax.swing.tree.DefaultMutableTreeNode;

import org.eclipse.persistence.tools.workbench.framework.Application;
import org.eclipse.persistence.tools.workbench.framework.context.PreferencesContext;
import org.eclipse.persistence.tools.workbench.framework.context.WorkbenchContext;
import org.eclipse.persistence.tools.workbench.framework.help.HelpManager;
import org.eclipse.persistence.tools.workbench.framework.resources.ResourceRepository;


/**
 * We subclass DefaultMutableTreeNode because preferences nodes are
 * static. We cache the nodes label text and properties page.
 */
public abstract class AbstractPreferencesNode
    extends DefaultMutableTreeNode
    implements PreferencesNode
{
    protected String displayString;
    protected Component propertiesPage;


    // ********** constructors/initialization **********

    /**
     * Construct a node with the specified context.
     * Subclasses can wrap the context in their constructors
     * before calling super(PreferencesContext).
     */
    protected AbstractPreferencesNode(PreferencesContext context) {
        // store the context in the node's "user object"
        super(context);
        this.initialize();
    }

    protected void initialize() {
        // allow subclasses to override and add sub-nodes etc.
    }


    // ********** EditorNode implementation **********

    /**
     * postpone building the properties page until it is first needed,
     * then cache it; this also allows us to have any extra state in
     * place before building the page
     * @see EditorNode#propertiesPage(WorkbenchContext)
     */
    public Component propertiesPage(WorkbenchContext workbenchContext) {
        if (this.propertiesPage == null) {
            this.propertiesPage = this.buildPropertiesPage();
        }
        return this.propertiesPage;
    }

    /**
     * This method will only be called if the cached properties
     * page is missing.
     */
    protected abstract Component buildPropertiesPage();

    /**
     * @see EditorNode#propertiesPageIcon()
     */
    public Icon propertiesPageTitleIcon() {
        return null;
    }

    /**
     * @see EditorNode#propertiesPageTitle()
     */
    public String propertiesPageTitleText() {
        return this.displayString();
    }

    /**
     * since there is only one preferences view, we do not need
     * to share the properties page
     * @see EditorNode#releasePropertiesPage(java.awt.Component)
     */
    public void releasePropertiesPage(Component page) {
        // do nothing
    }


    // ********** PreferencesNode implementation **********

    /**
     * @see PreferencesNode#getPreferences()
     */
    public Preferences getPreferences() {
        return this.getPreferencesContext().getPreferences();
    }

    /**
     * postpone building the display string until it is first needed,
     * then cache it; this also allows us to have any extra state in
     * place before building the string
     * @see PreferencesNode#displayString()
     */
    public String displayString() {
        if (this.displayString == null) {
            this.displayString = this.buildDisplayString();
        }
        return this.displayString;
    }

    /**
     * This method will only be called if the cached display
     * string is missing.
     */
    protected abstract String buildDisplayString();

    /**
     * @see PreferencesNode#helpTopicId()
     */
    public String helpTopicId() {
        return null;
    }


    // ********** queries **********

    /**
     * convenience method - cast the node's "user object"
     */
    protected PreferencesContext getPreferencesContext() {
        return (PreferencesContext) this.getUserObject();
    }

    protected Application application() {
        return this.getPreferencesContext().getApplication();
    }

    protected Preferences preferences() {
        return this.getPreferencesContext().getPreferences();
    }

    public ResourceRepository resourceRepository() {
        return this.getPreferencesContext().getResourceRepository();
    }

    protected HelpManager helpManager() {
        return this.getPreferencesContext().getHelpManager();
    }

    public void showHelp() {
        this.helpManager().showTopic(this.helpTopicId());
    }
}