{"id":1746,"date":"2014-11-09T15:34:02","date_gmt":"2014-11-09T13:34:02","guid":{"rendered":"http:\/\/hasselba.ch\/blog\/?p=1746"},"modified":"2014-11-09T15:34:02","modified_gmt":"2014-11-09T13:34:02","slug":"xpages-running-googles-chrome-v8-javascript-engine","status":"publish","type":"post","link":"https:\/\/hasselba.ch\/blog\/?p=1746","title":{"rendered":"XPages: Running Google’s Chrome V8 Javascript Engine"},"content":{"rendered":"

After answering a question on Stackoverflow.com<\/a> about the Prototype problematic in the XPages SSJS engine<\/a>, I thought of running another Javascript engine on top of Domino.<\/p>\n

While you can use the JavaScripting API JSR223, I choosed the jav8 project<\/a> for a test how this can be realized. So I downloaded the Windows binaries to get the required DLL and imported it into a new database. I also imported the source files of the lu.fler.script<\/em> package to recompile all required classes.<\/p>\n

Then, I registered the factory service by creating a javax.script.ScriptEngineFactory<\/em> file in the \/META-INF\/services<\/em> folder and added the line lu.flier.script.V8ScriptEngineFactory<\/em>.<\/p>\n

\"\"<\/p>\n

The package explorer looked like this:<\/p>\n

\"\"<\/p>\n

To prevent collisions, I commented out some names in the V8ScriptEngineFactory<\/em> class:<\/p>\n

\"\"<\/p>\n

For a simple test, I decided to invoke the engine manually when clicking on a button on a XPage. To do this, I created a simple ActionListener in Java which loads the JavaScript Engine and evals a simple “ var i = 1+1″. The Javascript variable is then accessed and printed out to the server console.<\/p>\n

package ch.hasselba.xpages.jav8;\r\n\r\nimport javax.faces.event.AbortProcessingException;\r\nimport javax.faces.event.ActionEvent;\r\nimport javax.script.ScriptEngine;\r\nimport javax.script.ScriptEngineManager;\r\nimport javax.script.ScriptException;\r\n\r\npublic class JAV8Test implements javax.faces.event.ActionListener {\r\n\r\n\u00a0\u00a0 \u00a0static ScriptEngineManager factory = new ScriptEngineManager();\r\n\u00a0\u00a0 \u00a0static ScriptEngine engine = factory.getEngineByName(\"jav8\");\r\n\r\n\u00a0\u00a0 \u00a0public void processAction(ActionEvent actionEvent)\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0throws AbortProcessingException {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0try {\r\n            System.out.println( engine.getClass().getCanonicalName() );\r\n            engine.eval(\"var i=1+1;\");\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0System.out.println( \"i = \" + engine.get(\"i\") );\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0} catch (ScriptException ex) {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0ex.printStackTrace();\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0}\r\n\u00a0\u00a0 \u00a0}\r\n}<\/code><\/pre>\n
The XPage to test the ActionListener is rather simple too:<\/p>\n
<?xml version=\"1.0\" encoding=\"UTF-8\"?>\r\n<xp:view xmlns:xp=\"http:\/\/www.ibm.com\/xsp\/core\">\r\n\r\n\u00a0\u00a0 \u00a0<xp:button\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0value=\"Click Me!\"\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0id=\"buttonClickMe\">\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0<xp:eventHandler\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0event=\"onclick\"\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0submit=\"true\"\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0refreshMode=\"complete\">\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0<xp:this.actionListeners>\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0     <xp:actionListener type=\"ch.hasselba.xpages.jav8.JAV8Test\" \/>\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0<\/xp:this.actionListeners>\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0<\/xp:eventHandler>\r\n\u00a0\u00a0 \u00a0<\/xp:button>\r\n\u00a0\u00a0 \u00a0\r\n<\/xp:view><\/code><\/pre>\n
When the button is clicked, the V8 engine works as it should:
\n\"\"<\/p>\n
But now comes a hard problems: It works only once! After doing this, my test server crashes completly. During playing with it, I was able to run it as it should, but I have no idea anymore how I did it. I think it is the DLL and static classes, but I am currently to busy to investigate the problem further. The @Override<\/em> notations added to the methods (which must removed before the code can be compiled) do not override exitisting ones (I checked the bundled javax.script<\/em> JAR of the binary package), this does not seem to be the problem. Maybe someone else has an idea?<\/p>\n","protected":false},"excerpt":{"rendered":"
After answering a question on Stackoverflow.com about the Prototype problematic in the XPages SSJS engine, I thought of running another Javascript engine on top of Domino. While you can use the JavaScripting API JSR223, I choosed the jav8 project for … Weiterlesen →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,76,74],"tags":[47,7,11,31,5,3],"class_list":["post-1746","post","type-post","status-publish","format-standard","hentry","category-allgemein","category-ssjs","category-xpages","tag-9-0","tag-domino","tag-http","tag-java","tag-ssjs","tag-xpages"],"_links":{"self":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1746","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1746"}],"version-history":[{"count":6,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1746\/revisions"}],"predecessor-version":[{"id":1752,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1746\/revisions\/1752"}],"wp:attachment":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1746"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1746"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1746"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}