/**

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

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  * General Public License Version 2 only ("GPL") or the Common

  * Development and Distribution License("CDDL") (collectively, the

  * "License"). You may not use this file except in compliance with the

  * License. You can obtain a copy of the License at

  * http://www.netbeans.org/cddl-gplv2.html

  * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the

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  * License Header, with the fields enclosed by brackets [] replaced by

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  * Contributor(s):

  *

  * The Original Software is NetBeans. The Initial Developer of the Original

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  *

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 package org.netbeans.html.boot.impl;

 import java.io.Closeable;

 import java.io.IOException;

 import java.util.logging.Logger;

 import org.apidesign.html.boot.spi.Fn;

 /**

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  */

 public final class FnContext implements Closeable {

     private static final Logger LOG = Logger.getLogger(FnContext.class.getName());

     private Object prev;

     private FnContext(Fn.Presenter p) {

         this.prev = p;

     }

     @Override

     public void close() throws IOException {

         if (prev != this) {

             currentPresenter((Fn.Presenter)prev);

             prev = this;

         }

     }

 /*

     @Override

     protected void finalize() throws Throwable {

         if (prev != null) {

             LOG.warning("Unclosed context!");

         }

     }

 */

     public static Closeable activate(Fn.Presenter newP) {

         return new FnContext(currentPresenter(newP));

     }

     private static final ThreadLocal<Fn.Presenter> CURRENT = new ThreadLocal<Fn.Presenter>();

     public static Fn.Presenter currentPresenter(Fn.Presenter p) {

         Fn.Presenter prev = CURRENT.get();

         CURRENT.set(p);

         return prev;

     }

     public static Fn.Presenter currentPresenter(boolean fail) {

         Fn.Presenter p = CURRENT.get();

         if (p == null && fail) {

             throw new IllegalStateException("No current WebView context around!");

         }

         return p;

     }

 }