improved the restart by using AJAX. See http://d.hatena.ne.jp/ssogabe/20090506/1241552799

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@17794 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/model/Hudson.java

@@ -2750,21 +2750,36 @@ public final class Hudson extends Node implements ItemGroup<TopLevelItem>, Stapl
 
     /**
      * Perform a restart of Hudson, if we can.
+     *
+     * This first replaces "app" to {@link HudsonIsRestarting}
      */
     public void doRestart(StaplerRequest req, StaplerResponse rsp) throws IOException, ServletException {
-        requirePOST();
         checkPermission(ADMINISTER);
-        try {
-            Lifecycle.get().restart();
-            servletContext.setAttribute("app",new HudsonIsRestarting());
-            rsp.sendRedirect2(".");
-        } catch (UnsupportedOperationException e) {
-            sendError("Restart is not supported in this running mode.",req,rsp);
-        } catch (IOException e) {
-            sendError(e,req,rsp);
-        } catch (InterruptedException e) {
-            sendError(e,req,rsp);
+        if(Stapler.getCurrentRequest().getMethod().equals("GET")) {
+            req.getView(this,"_restart.jelly").forward(req,rsp);
+            return;
         }
+
+        final Lifecycle lifecycle = Lifecycle.get();
+        if(!lifecycle.canRestart())
+            sendError("Restart is not supported in this running mode.",req,rsp);
+        servletContext.setAttribute("app",new HudsonIsRestarting());
+        rsp.sendRedirect2(".");
+
+        new Thread("restart thread") {
+            @Override
+            public void run() {
+                try {
+                    // give some time for the browser to load the "reloading" page
+                    Thread.sleep(5000);
+                    lifecycle.restart();
+                } catch (InterruptedException e) {
+                    LOGGER.log(Level.WARNING, "Failed to restart Hudson",e);
+                } catch (IOException e) {
+                    LOGGER.log(Level.WARNING, "Failed to restart Hudson",e);
+                }
+            }
+        }.start();
     }
 
     /**

core/src/main/resources/hudson/model/Hudson/_restart.jelly

+<!--
+The MIT License
+
+Copyright (c) 2004-2009, Sun Microsystems, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+-->
+
+<!-- Delete view -->
+<j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form" xmlns:i="jelly:fmt">
+	<l:layout title="Restart Hudson">
+		<st:include page="sidepanel.jelly" />
+		<l:main-panel>
+		  <form method="post" action="restart">
+		    ${%Are you sure about restarting Hudson?}
+		    <f:submit value="${%Yes}" />
+		  </form>
+		</l:main-panel>
+	</l:layout>
+</j:jelly>
\ No newline at end of file

war/resources/scripts/hudson-behavior.js

@@ -1482,7 +1482,12 @@ function applySafeRedirector(url) {
                 }
             },
             onSuccess: function(rsp) {
-                window.location.replace(url);
+                if(rsp.status!=200) {
+                    // if connection fails, somehow Prototype thinks it's a success
+                    window.setTimeout(statusChecker,5000);
+                } else {
+                    window.location.replace(url);
+                }
             }
         });
     }, 5000);