user/src/com/google/gwt/user/client/Window.java - gwt - Git at Google

 /*
  * Copyright 2008 Google Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License. You may obtain a copy of
  * the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  * License for the specific language governing permissions and limitations under
  * the License.
  */
 package com.google.gwt.user.client;

 import com.google.gwt.core.client.GWT;
 import com.google.gwt.core.client.GWT.UncaughtExceptionHandler;
 import com.google.gwt.http.client.URL;
 import com.google.gwt.user.client.impl.WindowImpl;

 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 /**
  * This class provides access to the browser window's methods, properties, and
  * events.
  */
 public class Window {

   /**
    * This class provides access to the browser's location's object. The location
    * object contains information about the current URL and methods to manipulate
    * it. <code>Location</code> is a very simple wrapper, so not all browser
    * quirks are hidden from the user.
    *
    */
   public static class Location {
     private static Map<String, String> paramMap;
     private static Map<String, List<String>> listParamMap;

     /**
      * Assigns the window to a new URL. All GWT state will be lost.
      *
      * @param newURL the new URL
      */
     public static native void assign(String newURL) /*-{
       $wnd.location.assign(newURL);
     }-*/;

     /**
      * Gets the string to the right of the URL's hash.
      *
      * @return the string to the right of the URL's hash.
      */

     public static String getHash() {
       return impl.getHash();
     }

     /**
      * Gets the URL's host and port name.
      *
      * @return the host and port name
      */
     public static native String getHost() /*-{
       return $wnd.location.host;
     }-*/;

     /**
      * Gets the URL's host name.
      *
      * @return the host name
      */
     public static native String getHostName() /*-{
       return $wnd.location.hostname;
     }-*/;

     /**
      * Gets the entire URL.
      *
      * @return the URL
      */
     public static native String getHref() /*-{
       return $wnd.location.href;
     }-*/;

     /**
      * Gets the URL's parameter of the specified name. Note that if multiple
      * parameters have been specified with the same name, the last one will
      * be returned.
      *
      * @param name the name of the URL's parameter
      * @return the value of the URL's parameter
      */
     public static String getParameter(String name) {
       ensureParameterMap();
       return paramMap.get(name);
     }

     /**
      * Returns a Map of the URL query parameters for the host page; since
      * changing the map would not change the window's location, the map returned
      * is immutable.
      *
      * @return a map from URL query parameter names to a list of values
      */
     public static Map<String, List<String>> getParameterMap() {
       if (listParamMap == null) {
         listParamMap = buildListParamMap(getQueryString());
       }
       return listParamMap;
     }

     /**
      * Gets the path to the URL.
      *
      * @return the path to the URL.
      */
     public static native String getPath() /*-{
       return $wnd.location.pathname;
     }-*/;

     /**
      * Gets the URL's port.
      *
      * @return the URL's port
      */
     public static native String getPort() /*-{
       return $wnd.location.port;
     }-*/;

     /**
      * Gets the URL's protocol.
      *
      * @return the URL's protocol.
      */
     public static native String getProtocol() /*-{
       return $wnd.location.protocol;
     }-*/;

     /**
      * Gets the URL's query string.
      *
      * @return the URL's query string
      */
     public static String getQueryString() {
       return impl.getQueryString();
     }

     /**
      * Reloads the current browser window. All GWT state will be lost.
      */
     public static native void reload() /*-{
       $wnd.location.reload();
     }-*/;

     /**
      * Replaces the current URL with a new one. All GWT state will be lost. In
      * the browser's history, the current URL will be replaced by the new URL.
      *
      * @param newURL the new URL
      */
     public static native void replace(String newURL) /*-{
       $wnd.location.replace(newURL);
     }-*/;

     /**
      * Builds the immutable map from String to List<String> that we'll return
      * in getParameterMap(). Package-protected for testing.
      * @return a map from the
      */
     static Map<String,List<String>> buildListParamMap(String queryString) {
       Map<String,List<String>> out = new HashMap<String, List<String>>();

       if (queryString != null && queryString.length() > 1) {
         String qs = queryString.substring(1);

         for (String kvPair : qs.split("&")) {
           String[] kv = kvPair.split("=", 2);
           if (kv[0].length() == 0) {
             continue;
           }

           List<String> values = out.get(kv[0]);
           if (values == null) {
             values = new ArrayList<String>();
             out.put(kv[0], values);
           }
           values.add(kv.length > 1 ? URL.decode(kv[1]) : "");
         }
       }

       for (Map.Entry<String, List<String>> entry : out.entrySet()) {
         entry.setValue(Collections.unmodifiableList(entry.getValue()));
       }

       out = Collections.unmodifiableMap(out);

       return out;
     }

     private static void ensureParameterMap() {
       if (paramMap == null) {
         paramMap = new HashMap<String, String>();
         String queryString = getQueryString();
         if (queryString != null && queryString.length() > 1) {
           String qs = queryString.substring(1);
           for (String kvPair : qs.split("&")) {
             String[] kv = kvPair.split("=", 2);
             if (kv.length > 1) {
               paramMap.put(kv[0], URL.decode(kv[1]));
             } else {
               paramMap.put(kv[0], "");
             }
           }
         }
       }
     }

     private Location() {
     }
   }

   private static boolean handlersAreInitialized;
   private static final WindowImpl impl = GWT.create(WindowImpl.class);

   private static ArrayList<WindowCloseListener> closingListeners;
   private static ArrayList<WindowResizeListener> resizeListeners;

   /**
    * Adds a listener to receive window closing events.
    *
    * @param listener the listener to be informed when the window is closing
    */
   public static void addWindowCloseListener(WindowCloseListener listener) {
     maybeInitializeHandlers();
     if (closingListeners == null) {
       closingListeners = new ArrayList<WindowCloseListener>();
     }
     closingListeners.add(listener);
   }

   /**
    * Adds a listener to receive window resize events.
    *
    * @param listener the listener to be informed when the window is resized
    */
   public static void addWindowResizeListener(WindowResizeListener listener) {
     maybeInitializeHandlers();
     if (resizeListeners == null) {
       resizeListeners = new ArrayList<WindowResizeListener>();
     }
     resizeListeners.add(listener);
   }

   /**
    * Displays a message in a modal dialog box.
    *
    * @param msg the message to be displayed.
    */
   public static native void alert(String msg) /*-{
     $wnd.alert(msg);
   }-*/;

   /**
    * Displays a message in a modal dialog box, along with the standard 'OK' and
    * 'Cancel' buttons.
    *
    * @param msg the message to be displayed.
    * @return <code>true</code> if 'OK' is clicked, <code>false</code> if
    *         'Cancel' is clicked.
    */
   public static native boolean confirm(String msg) /*-{
     return $wnd.confirm(msg);
   }-*/;

   /**
    * Use this method to explicitly disable the window's scrollbars. Applications
    * that choose to resize their user-interfaces to fit within the window's
    * client area will normally want to disable window scrolling.
    *
    * @param enable <code>false</code> to disable window scrolling
    */
   public static void enableScrolling(boolean enable) {
     impl.enableScrolling(enable);
   }

   /**
    * Gets the height of the browser window's client area excluding the scroll
    * bar.
    *
    * @return the window's client height
    */
   public static int getClientHeight() {
     return impl.getClientHeight();
   }

   /**
    * Gets the width of the browser window's client area excluding the vertical
    * scroll bar.
    *
    * @return the window's client width
    */
   public static int getClientWidth() {
     return impl.getClientWidth();
   }

   /**
    * Gets the window's scroll left.
    *
    * @return window's scroll left
    */
   public static int getScrollLeft() {
     return impl.getScrollLeft();
   }

   /**
    * Get the window's scroll top.
    *
    * @return the window's scroll top
    */
   public static int getScrollTop() {
     return impl.getScrollTop();
   }

   /**
    * Gets the browser window's current title.
    *
    * @return the window's title.
    */
   public static native String getTitle() /*-{
     return $doc.title;
   }-*/;

   /**
    * Opens a new browser window. The "name" and "features" arguments are
    * specified <a href=
    * 'http://www.mozilla.org/docs/dom/domref/dom_window_ref76.html'>here</a>.
    *
    * @param url the URL that the new window will display
    * @param name the name of the window (e.g. "_blank")
    * @param features the features to be enabled/disabled on this window
    */
   public static native void open(String url, String name, String features) /*-{
     $wnd.open(url, name, features);
   }-*/;

   /**
    * Prints the document in the window, as if the user had issued a "Print"
    * command.
    */
   public static native void print() /*-{
     $wnd.print();
   }-*/;

   /**
    * Displays a request for information in a modal dialog box, along with the
    * standard 'OK' and 'Cancel' buttons.
    *
    * @param msg the message to be displayed
    * @param initialValue the initial value in the dialog's text field
    * @return the value entered by the user if 'OK' was pressed, or
    *         <code>null</code> if 'Cancel' was pressed
    */
   public static native String prompt(String msg, String initialValue) /*-{
     return $wnd.prompt(msg, initialValue);
   }-*/;

   /**
    * Removes a window closing listener.
    *
    * @param listener the listener to be removed
    */
   public static void removeWindowCloseListener(WindowCloseListener listener) {
     if (closingListeners != null) {
       closingListeners.remove(listener);
     }
   }

   /**
    * Removes a window resize listener.
    *
    * @param listener the listener to be removed
    */
   public static void removeWindowResizeListener(WindowResizeListener listener) {
     if (resizeListeners != null) {
       resizeListeners.remove(listener);
     }
   }

   /**
    * Sets the size of the margins used within the window's client area. It is
    * sometimes necessary to do this because some browsers, such as Internet
    * Explorer, add margins by default, which can confound attempts to resize
    * panels to fit exactly within the window.
    *
    * @param size the window's new margin size, in CSS units.
    */
   public static native void setMargin(String size) /*-{
     $doc.body.style.margin = size;
   }-*/;

   /**
    * Sets the status text for the window. Calling this method in Firefox has no
    * effect.
    *
    * @param status the new message to display.
    */
   public static native void setStatus(String status) /*-{
     $wnd.status = status;
   }-*/;

   /**
    * Sets the browser window's title.
    *
    * @param title the new window title.
    */
   public static native void setTitle(String title) /*-{
     $doc.title = title;
   }-*/;

   static void onClosed() {
     UncaughtExceptionHandler handler = GWT.getUncaughtExceptionHandler();
     if (handler != null) {
       fireClosedAndCatch(handler);
     } else {
       fireClosedImpl();
     }
   }

   static String onClosing() {
     UncaughtExceptionHandler handler = GWT.getUncaughtExceptionHandler();
     if (handler != null) {
       return fireClosingAndCatch(handler);
     } else {
       return fireClosingImpl();
     }
   }

   static void onResize() {
     UncaughtExceptionHandler handler = GWT.getUncaughtExceptionHandler();
     if (handler != null) {
       fireResizedAndCatch(handler);
     } else {
       fireResizedImpl();
     }
   }

   private static void fireClosedAndCatch(UncaughtExceptionHandler handler) {
     try {
       fireClosedImpl();
     } catch (Throwable e) {
       handler.onUncaughtException(e);
     }
   }

   private static void fireClosedImpl() {
     if (closingListeners != null) {
       for (WindowCloseListener listener : closingListeners) {
         listener.onWindowClosed();
       }
     }
   }

   private static String fireClosingAndCatch(UncaughtExceptionHandler handler) {
     try {
       return fireClosingImpl();
     } catch (Throwable e) {
       handler.onUncaughtException(e);
       return null;
     }
   }

   private static String fireClosingImpl() {
     String ret = null;
     if (closingListeners != null) {
       for (WindowCloseListener listener : closingListeners) {
         // If any listener wants to suppress the window closing event, then do
         // so.
         String msg = listener.onWindowClosing();
         if (ret == null) {
           ret = msg;
         }
       }
     }

     return ret;
   }

   private static void fireResizedAndCatch(UncaughtExceptionHandler handler) {
     try {
       fireResizedImpl();
     } catch (Throwable e) {
       handler.onUncaughtException(e);
     }
   }

   private static void fireResizedImpl() {
     if (resizeListeners != null) {
       for (WindowResizeListener listener : resizeListeners) {
         listener.onWindowResized(getClientWidth(), getClientHeight());
       }
     }
   }

   private static native void init() /*-{
     // Magic function defined by the selection script.
     __gwt_initHandlers(
       function() {
         @com.google.gwt.user.client.Window::onResize()();
       },
       function() {
         return @com.google.gwt.user.client.Window::onClosing()();
       },
       function() {
         @com.google.gwt.user.client.Window::onClosed()();
       }
     );
   }-*/;

   private static void maybeInitializeHandlers() {
     if (GWT.isClient() && !handlersAreInitialized) {
       init();
       handlersAreInitialized = true;
     }
   }

   private Window() {
   }
 }
	/*
	* Copyright 2008 Google Inc.
	*
	* Licensed under the Apache License, Version 2.0 (the "License"); you may not
	* use this file except in compliance with the License. You may obtain a copy of
	* the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
	* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
	* License for the specific language governing permissions and limitations under
	* the License.
	*/
	package com.google.gwt.user.client;

	import com.google.gwt.core.client.GWT;
	import com.google.gwt.core.client.GWT.UncaughtExceptionHandler;
	import com.google.gwt.http.client.URL;
	import com.google.gwt.user.client.impl.WindowImpl;

	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;

	/**
	* This class provides access to the browser window's methods, properties, and
	* events.
	*/
	public class Window {

	/**
	* This class provides access to the browser's location's object. The location
	* object contains information about the current URL and methods to manipulate
	* it. <code>Location</code> is a very simple wrapper, so not all browser
	* quirks are hidden from the user.
	*
	*/
	public static class Location {
	private static Map<String, String> paramMap;
	private static Map<String, List<String>> listParamMap;

	/**
	* Assigns the window to a new URL. All GWT state will be lost.
	*
	* @param newURL the new URL
	*/
	public static native void assign(String newURL) /*-{
	$wnd.location.assign(newURL);
	}-*/;

	/**
	* Gets the string to the right of the URL's hash.
	*
	* @return the string to the right of the URL's hash.
	*/

	public static String getHash() {
	return impl.getHash();
	}

	/**
	* Gets the URL's host and port name.
	*
	* @return the host and port name
	*/
	public static native String getHost() /*-{
	return $wnd.location.host;
	}-*/;

	/**
	* Gets the URL's host name.
	*
	* @return the host name
	*/
	public static native String getHostName() /*-{
	return $wnd.location.hostname;
	}-*/;

	/**
	* Gets the entire URL.
	*
	* @return the URL
	*/
	public static native String getHref() /*-{
	return $wnd.location.href;
	}-*/;

	/**
	* Gets the URL's parameter of the specified name. Note that if multiple
	* parameters have been specified with the same name, the last one will
	* be returned.
	*
	* @param name the name of the URL's parameter
	* @return the value of the URL's parameter
	*/
	public static String getParameter(String name) {
	ensureParameterMap();
	return paramMap.get(name);
	}

	/**
	* Returns a Map of the URL query parameters for the host page; since
	* changing the map would not change the window's location, the map returned
	* is immutable.
	*
	* @return a map from URL query parameter names to a list of values
	*/
	public static Map<String, List<String>> getParameterMap() {
	if (listParamMap == null) {
	listParamMap = buildListParamMap(getQueryString());
	}
	return listParamMap;
	}

	/**
	* Gets the path to the URL.
	*
	* @return the path to the URL.
	*/
	public static native String getPath() /*-{
	return $wnd.location.pathname;
	}-*/;

	/**
	* Gets the URL's port.
	*
	* @return the URL's port
	*/
	public static native String getPort() /*-{
	return $wnd.location.port;
	}-*/;

	/**
	* Gets the URL's protocol.
	*
	* @return the URL's protocol.
	*/
	public static native String getProtocol() /*-{
	return $wnd.location.protocol;
	}-*/;

	/**
	* Gets the URL's query string.
	*
	* @return the URL's query string
	*/
	public static String getQueryString() {
	return impl.getQueryString();
	}

	/**
	* Reloads the current browser window. All GWT state will be lost.
	*/
	public static native void reload() /*-{
	$wnd.location.reload();
	}-*/;

	/**
	* Replaces the current URL with a new one. All GWT state will be lost. In
	* the browser's history, the current URL will be replaced by the new URL.
	*
	* @param newURL the new URL
	*/
	public static native void replace(String newURL) /*-{
	$wnd.location.replace(newURL);
	}-*/;

	/**
	* Builds the immutable map from String to List<String> that we'll return
	* in getParameterMap(). Package-protected for testing.
	* @return a map from the
	*/
	static Map<String,List<String>> buildListParamMap(String queryString) {
	Map<String,List<String>> out = new HashMap<String, List<String>>();

	if (queryString != null && queryString.length() > 1) {
	String qs = queryString.substring(1);

	for (String kvPair : qs.split("&")) {
	String[] kv = kvPair.split("=", 2);
	if (kv[0].length() == 0) {
	continue;
	}

	List<String> values = out.get(kv[0]);
	if (values == null) {
	values = new ArrayList<String>();
	out.put(kv[0], values);
	}
	values.add(kv.length > 1 ? URL.decode(kv[1]) : "");
	}
	}

	for (Map.Entry<String, List<String>> entry : out.entrySet()) {
	entry.setValue(Collections.unmodifiableList(entry.getValue()));
	}

	out = Collections.unmodifiableMap(out);

	return out;
	}

	private static void ensureParameterMap() {
	if (paramMap == null) {
	paramMap = new HashMap<String, String>();
	String queryString = getQueryString();
	if (queryString != null && queryString.length() > 1) {
	String qs = queryString.substring(1);
	for (String kvPair : qs.split("&")) {
	String[] kv = kvPair.split("=", 2);
	if (kv.length > 1) {
	paramMap.put(kv[0], URL.decode(kv[1]));
	} else {
	paramMap.put(kv[0], "");
	}
	}
	}
	}
	}

	private Location() {
	}
	}

	private static boolean handlersAreInitialized;
	private static final WindowImpl impl = GWT.create(WindowImpl.class);

	private static ArrayList<WindowCloseListener> closingListeners;
	private static ArrayList<WindowResizeListener> resizeListeners;

	/**
	* Adds a listener to receive window closing events.
	*
	* @param listener the listener to be informed when the window is closing
	*/
	public static void addWindowCloseListener(WindowCloseListener listener) {
	maybeInitializeHandlers();
	if (closingListeners == null) {
	closingListeners = new ArrayList<WindowCloseListener>();
	}
	closingListeners.add(listener);
	}

	/**
	* Adds a listener to receive window resize events.
	*
	* @param listener the listener to be informed when the window is resized
	*/
	public static void addWindowResizeListener(WindowResizeListener listener) {
	maybeInitializeHandlers();
	if (resizeListeners == null) {
	resizeListeners = new ArrayList<WindowResizeListener>();
	}
	resizeListeners.add(listener);
	}

	/**
	* Displays a message in a modal dialog box.
	*
	* @param msg the message to be displayed.
	*/
	public static native void alert(String msg) /*-{
	$wnd.alert(msg);
	}-*/;

	/**
	* Displays a message in a modal dialog box, along with the standard 'OK' and
	* 'Cancel' buttons.
	*
	* @param msg the message to be displayed.
	* @return <code>true</code> if 'OK' is clicked, <code>false</code> if
	* 'Cancel' is clicked.
	*/
	public static native boolean confirm(String msg) /*-{
	return $wnd.confirm(msg);
	}-*/;

	/**
	* Use this method to explicitly disable the window's scrollbars. Applications
	* that choose to resize their user-interfaces to fit within the window's
	* client area will normally want to disable window scrolling.
	*
	* @param enable <code>false</code> to disable window scrolling
	*/
	public static void enableScrolling(boolean enable) {
	impl.enableScrolling(enable);
	}

	/**
	* Gets the height of the browser window's client area excluding the scroll
	* bar.
	*
	* @return the window's client height
	*/
	public static int getClientHeight() {
	return impl.getClientHeight();
	}

	/**
	* Gets the width of the browser window's client area excluding the vertical
	* scroll bar.
	*
	* @return the window's client width
	*/
	public static int getClientWidth() {
	return impl.getClientWidth();
	}

	/**
	* Gets the window's scroll left.
	*
	* @return window's scroll left
	*/
	public static int getScrollLeft() {
	return impl.getScrollLeft();
	}

	/**
	* Get the window's scroll top.
	*
	* @return the window's scroll top
	*/
	public static int getScrollTop() {
	return impl.getScrollTop();
	}

	/**
	* Gets the browser window's current title.
	*
	* @return the window's title.
	*/
	public static native String getTitle() /*-{
	return $doc.title;
	}-*/;

	/**
	* Opens a new browser window. The "name" and "features" arguments are
	* specified <a href=
	* 'http://www.mozilla.org/docs/dom/domref/dom_window_ref76.html'>here</a>.
	*
	* @param url the URL that the new window will display
	* @param name the name of the window (e.g. "_blank")
	* @param features the features to be enabled/disabled on this window
	*/
	public static native void open(String url, String name, String features) /*-{
	$wnd.open(url, name, features);
	}-*/;

	/**
	* Prints the document in the window, as if the user had issued a "Print"
	* command.
	*/
	public static native void print() /*-{
	$wnd.print();
	}-*/;

	/**
	* Displays a request for information in a modal dialog box, along with the
	* standard 'OK' and 'Cancel' buttons.
	*
	* @param msg the message to be displayed
	* @param initialValue the initial value in the dialog's text field
	* @return the value entered by the user if 'OK' was pressed, or
	* <code>null</code> if 'Cancel' was pressed
	*/
	public static native String prompt(String msg, String initialValue) /*-{
	return $wnd.prompt(msg, initialValue);
	}-*/;

	/**
	* Removes a window closing listener.
	*
	* @param listener the listener to be removed
	*/
	public static void removeWindowCloseListener(WindowCloseListener listener) {
	if (closingListeners != null) {
	closingListeners.remove(listener);
	}
	}

	/**
	* Removes a window resize listener.
	*
	* @param listener the listener to be removed
	*/
	public static void removeWindowResizeListener(WindowResizeListener listener) {
	if (resizeListeners != null) {
	resizeListeners.remove(listener);
	}
	}

	/**
	* Sets the size of the margins used within the window's client area. It is
	* sometimes necessary to do this because some browsers, such as Internet
	* Explorer, add margins by default, which can confound attempts to resize
	* panels to fit exactly within the window.
	*
	* @param size the window's new margin size, in CSS units.
	*/
	public static native void setMargin(String size) /*-{
	$doc.body.style.margin = size;
	}-*/;

	/**
	* Sets the status text for the window. Calling this method in Firefox has no
	* effect.
	*
	* @param status the new message to display.
	*/
	public static native void setStatus(String status) /*-{
	$wnd.status = status;
	}-*/;

	/**
	* Sets the browser window's title.
	*
	* @param title the new window title.
	*/
	public static native void setTitle(String title) /*-{
	$doc.title = title;
	}-*/;

	static void onClosed() {
	UncaughtExceptionHandler handler = GWT.getUncaughtExceptionHandler();
	if (handler != null) {
	fireClosedAndCatch(handler);
	} else {
	fireClosedImpl();
	}
	}

	static String onClosing() {
	UncaughtExceptionHandler handler = GWT.getUncaughtExceptionHandler();
	if (handler != null) {
	return fireClosingAndCatch(handler);
	} else {
	return fireClosingImpl();
	}
	}

	static void onResize() {
	UncaughtExceptionHandler handler = GWT.getUncaughtExceptionHandler();
	if (handler != null) {
	fireResizedAndCatch(handler);
	} else {
	fireResizedImpl();
	}
	}

	private static void fireClosedAndCatch(UncaughtExceptionHandler handler) {
	try {
	fireClosedImpl();
	} catch (Throwable e) {
	handler.onUncaughtException(e);
	}
	}

	private static void fireClosedImpl() {
	if (closingListeners != null) {
	for (WindowCloseListener listener : closingListeners) {
	listener.onWindowClosed();
	}
	}
	}

	private static String fireClosingAndCatch(UncaughtExceptionHandler handler) {
	try {
	return fireClosingImpl();
	} catch (Throwable e) {
	handler.onUncaughtException(e);
	return null;
	}
	}

	private static String fireClosingImpl() {
	String ret = null;
	if (closingListeners != null) {
	for (WindowCloseListener listener : closingListeners) {
	// If any listener wants to suppress the window closing event, then do
	// so.
	String msg = listener.onWindowClosing();
	if (ret == null) {
	ret = msg;
	}
	}
	}

	return ret;
	}

	private static void fireResizedAndCatch(UncaughtExceptionHandler handler) {
	try {
	fireResizedImpl();
	} catch (Throwable e) {
	handler.onUncaughtException(e);
	}
	}

	private static void fireResizedImpl() {
	if (resizeListeners != null) {
	for (WindowResizeListener listener : resizeListeners) {
	listener.onWindowResized(getClientWidth(), getClientHeight());
	}
	}
	}

	private static native void init() /*-{
	// Magic function defined by the selection script.
	__gwt_initHandlers(
	function() {
	@com.google.gwt.user.client.Window::onResize()();
	},
	function() {
	return @com.google.gwt.user.client.Window::onClosing()();
	},
	function() {
	@com.google.gwt.user.client.Window::onClosed()();
	}
	);
	}-*/;

	private static void maybeInitializeHandlers() {
	if (GWT.isClient() && !handlersAreInitialized) {
	init();
	handlersAreInitialized = true;
	}
	}

	private Window() {
	}
	}