Tech Views- Naga

Uploading multiple Files in J2EE application

2011-08-19T14:50:00.000-07:00

Uploading multiple files is less often a requirement and can be done in wide variety of ways

Some of the approaches are listed below for analysis
ActiveX control - there are many ready to use Active-X controls that can be used to upload.
http://www.aurigma.com/Products/ImageUploader/OnlineDemo.aspx
Using plain javascript to build file upload controls: refer to solution as in this link -
http://the-stickman.com/web-development/javascript/upload-multiple-files-with-a-single-file-element/
jFileChooser
jUpload
jumpLoader
Java Applet - Most of the multiple file uploads were done using the Java applet approach though the pain is to use the Signed applets.

Some other approaches are
http://ajaxian.com/archives/asynchronous-file-upload-with-yui
http://www.uploadify.com/

Exception in invoking the CXF Web services from WPS 6.1

2011-08-04T22:48:00.000-07:00

Getting the exception below while invoking the CXF web service using Websphere V 6.1 as the JRE from Eclipse
Aug 4, 2011 4:25:21 PM org.springframework.context.support.AbstractApplicationContext prepareRefresh

INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@39123912: startup date [Thu Aug 04 16:25:21 PDT 2011]; root of context hierarchy
Aug 4, 2011 4:25:21 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [cxf.xml]
Aug 4, 2011 4:25:22 PM org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
INFO: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@77be77be: defining beans [cxf,org.apache.cxf.bus.spring.BusWiringBeanFactoryPostProcessor,org.apache.cxf.bus.spring.Jsr250BeanPostProcessor,org.apache.cxf.bus.spring.BusExtensionPostProcessor,http://tools-dev........com/ssueect/services/.*]; root of factory hierarchy
In NHFEntitlementService.callNHFService method: BEGIN
Exception in thread "main" java.lang.NoClassDefFoundError: javax.xml.ws.Service
at com.......ws.client.NHFClient.(NHFClient.java:15)
at com.......nhf.service.NHFEntitlementService.callNHFService(NHFEntitlementService.java:20)
at com.......nhf.service.NHFEntitlementService.main(NHFEntitlementService.java:29)
Caused by: java.lang.ClassNotFoundException: javax.xml.ws.Service
at java.net.URLClassLoader.findClass(URLClassLoader.java:496)
at java.lang.ClassLoader.loadClass(ClassLoader.java:631)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
at java.lang.ClassLoader.loadClass(ClassLoader.java:597)
... 3 more

But am not getting this exception if I select JDK 6 as the JRE for running the same main method.

And the Log is as below when it is successful:

Aug 4, 2011 4:14:31 PM org.springframework.context.support.AbstractApplicationContext prepareRefresh

INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@62f662f6: startup date [Thu Aug 04 16:14:31 PDT 2011]; root of context hierarchy

Aug 4, 2011 4:14:31 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions

INFO: Loading XML bean definitions from class path resource [cxf.xml]

Aug 4, 2011 4:14:33 PM org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons

INFO: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@72a072a: defining beans [http://tools-dev............com/ssueect/services/.*]; root of factory hierarchy

In NHFEntitlementService.callNHFService method: BEGIN

Aug 4, 2011 4:14:33 PM org.springframework.context.support.AbstractApplicationContext prepareRefresh

INFO: Refreshing org.apache.cxf.bus.spring.BusApplicationContext@629f629f: startup date [Thu Aug 04 16:14:33 PDT 2011]; root of context hierarchy

Aug 4, 2011 4:14:33 PM org.apache.cxf.bus.spring.BusApplicationContext getConfigResources

INFO: Loaded configuration file cxf.xml.

Aug 4, 2011 4:14:33 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions

INFO: Loading XML bean definitions from class path resource [META-INF/cxf/cxf.xml]

Aug 4, 2011 4:14:33 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions

INFO: Loading XML bean definitions from class path resource [META-INF/cxf/cxf-extension-wstx-msv-validation.xml]

Aug 4, 2011 4:14:33 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions

INFO: Loading XML bean definitions from class path resource [cxf.xml]

Aug 4, 2011 4:14:33 PM org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons

INFO: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@7df17df1: defining beans [cxf,org.apache.cxf.bus.spring.BusWiringBeanFactoryPostProcessor,org.apache.cxf.bus.spring.Jsr250BeanPostProcessor,org.apache.cxf.bus.spring.BusExtensionPostProcessor,org.apache.cxf.wstx_msv_validation.WoodstoxValidationImpl,http://tools-dev............com/ssueect/services/.*]; root of factory hierarchy

Aug 4, 2011 4:14:33 PM org.apache.cxf.service.factory.ReflectionServiceFactoryBean buildServiceFromClass

INFO: Creating Service {http://tools-dev............com/ssueect/services/}NHFService from class com............nhf.ws.client.NHFWebService

{ r e s p o n s e d a t a h e r e }

In NHFEntitlementService.callNHFService method: END

DOJO specials

2010-11-24T00:11:00.000-08:00

one stop API reference for almost all DOJO needs

http://dojotoolkit.org/api/

CSS 3 test it yourself

2010-11-23T21:52:00.000-08:00

Very useful information and self-check of CSS styles in your browser...

http://tools.css3.info/selectors-test/test.html

Resolving the Form resubmission issue in Web application - Browser Back button issue

2010-11-23T11:13:00.000-08:00

I stumbled up on a very frequent issue to be faced by a web application developer - the Browser Back button issue.

Question is how can we handle the resubmission of forms when user clicking on the Browser Back button?

Following links have provided me a clue on getting pass by this: Synchronizer token is the simple answer to handle at server side. Gives idea on the generic Presentation Tier Design Considerations: http://www.corej2eepatterns.com/Design/PresoDesign.htm

Gives focus more on the issue giving example in Struts framework: http://www.java-samples.com/showtutorial.php?tutorialid=582

Generating the classpath in Manifest files using Ant Script

2010-11-23T11:09:00.000-08:00

I had a requirement to generate the classpath in Manifest files usng Ant Script and i found the link below to be very useful: http://martin.ankerl.com/2005/11/30/howto-create-manifestmf-classpath-from-ant/

The issue is discussed step by step in detail in this discussion: http://stackoverflow.com/questions/858766/generate-manifest-class-path-from-classpath-in-ant

Useful Links - Self Reference

2010-11-11T01:49:00.000-08:00

Some useful Links

Jquery Demo on Autocomplete textbox

http://jqueryui.com/demos/autocomplete/combobox.html

Interesting blog on website security

http://www.cmswire.com/cms/web-cms/how-they-hack-your-website-overview-of-common-techniques-002339.php

And a good ppt on how t ohack a web app with measures to be taken against such hacks

http://www.scribd.com/doc/2189835/9-Ways-to-Hack-a-Web-App

tag libs in 2.3 and 2.4 webapp

2010-04-17T11:27:00.000-07:00

Recently came across migrating the 2.3 Webapp to 2.4 webapp and one of new learning is to change the taglib directives.

Taglibs in web.xml of 2.3 is as below:

<taglib>
<taglib-uri>/spring</taglib-uri>
<taglib-location>/WEB-INF/lib/spring.tld</taglib-location>
</taglib>

To make the same tags work in 2.4 web-apps the above section should be encapsulated in tag <jsp-config> as given below.

<jsp-config>
<taglib>
<taglib-uri>/spring</taglib-uri>
<taglib-location>/WEB-INF/lib/spring.tld</taglib-location>
</taglib>
</jsp-config>

ref: http://forums.sun.com/thread.jspa?threadID=691985

Issue with Struts Portlet and Events in JSR 286

2010-04-09T15:00:00.000-07:00

Just came across the following link which says the Struts Portlet cannot use the Events feature of the JSR 286 specifications and hence the wires cannot be created.

The solution is to stick with JSR 168 specifications if the portlets are to be wired and use Struts portlet framework.

http://www-01.ibm.com/support/docview.wss?uid=swg21408727

Creating Sequence Diagrams Real Quick

2009-11-13T23:02:00.000-08:00

Thanks for this productivity hack from one of my collegue:
This site http://www.websequencediagrams.com/ allows very easy and intuitive algorithmic way of drawing sequence diagrams. We can just concentrate on the sequence of actions and not on the layout.

For example type the following algorithm in the site and see the result for yourself

Browser->Home.jsp: user clicks on home link
Home.jsp->HomeController:call doHomeAction
HomeController->HomeBO:get Home objects
HomeBO->HomeDAO: get Home DAO Objects
note right of HomeDAO: gets the data from Database.
HomeDAO->HomeBO: Return Home Dataset
HomeBO->HomeController:Return Home objects
HomeController->Home.jsp:Render the home page
Home.jsp->Browser: display Home page

Experimenting with PhotoFunia

2009-08-27T12:57:00.000-07:00

Quick checklist on differences between IBM Portlets and JSR Portlets - Part 1

2009-07-28T18:39:00.001-07:00

This article gives a quick reference for most of the differences between the IBM Portlets and JSR 168/286 portlets in Java source code.
This can also be used as a quick checklist if we frequently work on JSR portlets and have to look into a IBM portlet for troubleshooting or viceversa.

Specification	IBM Portlets implementation	JSR Portlets equivalent
Import statements to be used	import org.apache.jetspeed.portlet.; import org.apache.jetspeed.service.;	import javax.portlet.; import com.ibm.portal.portlet.service.;
Portlet Class inheritance	public class SampleIBMPortlet extends PortletAdapter implements ActionListener{ ... }	public class SampleJSRPortlet extends GenericPortlet{ ... }
Arguments to lifecycle methods like doView, doEdit, doHelp	public void doView(PortletRequest request, PortletResponse response) { ... }	public void doView(RenderRequest request, RenderResponse response) throws PortletException, IOException{ ... }
Action processing	public void actionPerformed(ActionEvent event) throws PortletException{ ... }	public void processAction(ActionRequest request, ActionResponse response) throws PortletException, IOException { ... }
Content type of Response	In IBM portlets the MIME type is set by using the JSP page directive so setting the contentType to response is not necessary.	response.setContentType("text/html"); This is required to be set in JSR portlets before including the JSP.
Dispatching to JSPs	PortletContext context = getPortletConfig().getContext(); context.include("/jsp/View.jsp", request, response);	response.setContentType("text/html"); PortletContext context = getPortletConfig().getPortletContext(); context.getRequestDispatcher("/jsp/View.jsp").include( request, response);
Accessing Portlet Preferences	PortletData portData = request.getData(); portData.setAttribute("userName", userName); portData.store();	PortletPreferences prefs = request.getPreferences(); prefs.setValue("userName",request.getParameter("username")); prefs.store();
Namespace encoding This method can be used to return unique string to be prefixed for portlet specific javascript functions.	PortletResponse.encodeNamespace()	RenderResponse.getNamespace()
URL generation	// Save URI for the edit page PortletURI editPageURI = response.createURI(); ... // Preserve the edit page URI in the request to make it accessible by the edit page JSP request.setAttribute("editPageURI", editPageURI.toString());	// Save URI for the edit page PortletURL editPageURL = response.createRenderURL(); ... // Preserve the edit page URI in the request to make it accessible by the edit JSP request.setAttribute("editPageURL", editPageURL.toString());

Ref: Source ref

Create animated GIF file from multiple images

2009-07-28T12:16:00.000-07:00

Ever see those animated Gif files which can display multiple images one after another?I wanted to have one for myself to put it in one of my blog and surprised to see that there is one very old small tool of microsoft that can be handy.

http://www.jhepple.com/gif_animator.htm

It served my purpose as my requirement is just to show the images one after the another. Quality of images that I used below are poor mainly due to get it quickly nature and due to lack of time, aloha comrades we are all running short of time at the end of day :)

If you do not want to install the freeware/shareware in your desktop. You can refer the online GIF creator web applications like
http://picasion.com/
http://www.gifninja.com/CreateAGif.aspx

Update: 24/May/2010 - All in all of the links above have limitations on the configuration parameters and mainly on the size of the animation files. The tool that resolved all of my issues and met requirements is http://www.photoscape.org

Portlet preferences getting shared across users JSR 286

2009-07-24T22:31:00.000-07:00

I have a JSR 168 porltet which I've recently upgraded to JSR 286 portlet specification. This portlet has some preferences. Users can change the portlet preferences and save them. These preferences should be user specific. This functionality was working fine in JSR 168.

But after upgrading to the JSR 286, this functionality is broken. The preferences stored by one userare shared for all the users. We are deploying the portlets in IBM Websphere Portal 6.1.x.

Changes made during the upgrade of JSR 168 to JSR 286

1) upgraded the portlet to JSR 286 specifications

2) The Edit View is now changed to be rendered over the AJAX through the 'serveResource' method. In essense the edit view is rendered while the portlet is still in VIEW mode and the preferences.store is called when the portlet is in VIEW mode.

One of the reference link on the issue: http://www-01.ibm.com/support/docview.wss?rs=688&uid=swg1PK30573

Debugging currently in progress.

Classpath compile errors for JAXBObject

2009-07-21T10:48:00.000-07:00

I am getting the exception below in RAD when I tried to compile a portlet project:

Description Resource Path Location Type

The type com.sun.xml.bind.JAXBObject cannot be resolved. It is indirectly referenced from required .class files UserAttributeBean.java FindProductPortlet/src/com/<comp_name>/<proj_name>/portlets/findproductportlet/bean line 1 Java Problem

Well this is a very basic exception and I've resolved it ample number of times, but at times, we tend to let loose the jar files names and search all the jar files for the file.

Fireworks effect using Javascript

2009-07-16T15:54:00.000-07:00

I was in need of the Fireworks effect in my personal blog. So searched the web for the javascripts that can emulate the fireworks in the web site.

After doing a quick search for about 5 mins, I finalized on the fireworks effect in the url
A big thanks to Stephen the javascript guide.

It works really cool, and allows triggering the start and stop events which i customized for the "Start" and "Stop" links in my personal blog.

Start Fireworks

I've just mimicked the start/stop behaviour here, Enjoy the Fireworks by clicking on the "Start Fireworks" link above.

Office 2010 - Preview Link

2009-07-14T08:26:00.000-07:00

One of the interesting article on Office 2010

http://www.winsupersite.com/office/office2010_tp.asp

you can always rely on the Microsoft's own link:

http://www.microsoft.com/office/2010/

URL Shorteners - quick post

2009-07-13T23:28:00.001-07:00

I was surprised to see some urls that my friend was using these days.

I was wondering how he is hosting his blog content from a diferent website altogether and still get a short url instead of a long one.

Any long url can be converted into a small url for example:

http://bit.ly/MkXu

is the short form of the long url: http://overview.mail.yahoo.com/products/new/recentchanges

The tiny url is definetely a better option to share with friends when sending in mails or blogs.

CONS:

The major con with this approach is that we are dependant on the unreliable middleman bit.ly or tinyurl.com for the redirection to your domain.

PROS:

The main advantage that I see is that the url shorteners like bit.ly provide a way of tracking the hits to any arbitrary url shared to the audience.

Upgrading JSR 168 portlets to JSR 286 specifications

2009-06-24T23:05:00.000-07:00

Recently we had to upgrade our JSR 168 portlets to JSR 286 specifications for utilizing the powerful features of JSR 286 mainly AJAX.

Following steps below outilne the minimal set of changes to be done for upgrading the portlets to JSR 286.

1. portlet.xml XSD reference changes

The portlet.xml should refer to the new xsd definitions.

<portlet-app xmlns="http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd"

version="1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd"

id="myportlet_app_id">

to be changed to

<portlet-app xmlns="http://java.sun.com/xml/ns/portlet/portlet-app_2_0.xsd"

version="2.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/portlet/portlet-app_2_0.xsd http://java.sun.com/xml/ns/portlet/portlet-app_2_0.xsd"

id="myportlet_app_id">

note the changes highlighted. So after these changes we will refer to the new specifications defined in _2_0 XSD files.

2. portlet.xml - add default namespace for portlet

Im JSR 286 portlets we need to give hte default name space for the portlet as in the line below.

<default-namespace>

http://com.mycomp.myproj.portlet.MyPortletName/

</default-namespace>

3. Tag library change in all JSP files

The portlet 1.0 tag library used in JSR 168 to be replaced with the portlet 2.0 tag library as defined in JSR 286 portlet.

Tag library in portlet 1.0 specification:

<%@taglib prefix="portlet" uri="http://java.sun.com/portlet"%>

Tag library in portlet 2.0 specification:

<%@taglib prefix="portlet" uri="http://java.sun.com/portlet_2_0"%>

Change all the JSPs in the portlet where tags are used.

This completes the minimal changes that are required for upgrading the JSR 168 portlets to JSR 286 portlets.

Getting Server name in a cluster - Websphere Solution

2008-12-08T23:24:00.000-08:00

When we work on a cluster environment of 2 or 3 nodes, Debugging an issue will become nightmare if we have to trace the recent page hit manually to a particular server name for looking logs.

Best way to attack this issue is by printing the server name as META data in the page HTML or to print the required information in HTML comments of the page.

You can use the code snippet below in a JSP page to print the server node name in a cluster.



Do not forget to add import statement as "com.ibm.websphere.runtime.ServerName".

:)

Blogging from Flock Browser

2008-09-24T18:27:00.001-07:00

Blogging from the Flock Browser.
A totally new experience of blogging.

I just downloaded the Flock browser and was going through the features.
One of the impressive features is to create new blog entries directly from the browser window with out even opening the blog site.

Download the Flock Broser
Login to your blogger account (Flock stores your account unless you signout)
Flock gives you the message that the browser is now configured to your blog account.
Click on the "Open Blog Editor" icon on the toolbar
(The toolbar is present just below your address bar)
And thats it, start writing the blog... and you can publish the blog entry from with in the browser window.

Blogged with the Flock Browser

Embed Picasa web private albums as Slide show into your Blog

2008-09-17T21:25:00.000-07:00

I was trying to share my picasa web album in my blog and was exploring the functionalities provided by Picasa.
Earlier I used to show the Album cover photo and manually give a link to it to point to the Slideshow url of the picasa album.
The New Embed feature is really very helpful as it allows viewing of the Picasa album from with in the site.

It all happens in few steps as below

1) Add photos to your Web album as you do regularly.
2) Open the Album by clicking on the album.
3) The Right Side bar will be displayed as below

4) Click on "Link to this album" link. The option for Embed slideshow is displayed as below:

If youdo not have "EN- US" as the language in your picase settings, then the "Embed Slideshow" option does not appear.

5) Click on the "Embed Slideshow" link. A dialog box opens as below

Select the options as you link, I always prefer to disable the "Autoplay" feature.

As it is the user of the site, who has to decide if a particuler media component has to be played automatically. Initially with out knowing this feature, I added six albums which resulted in un-acceptable behaviour as all sx albums started playing automatically.

6) Copy the HTML code snippet given in Step 5 and paste it into your blog.

Hurray, the process is done,,, and you now have the album that can be displayed as slideshow direcly on your site.

Embed Google Map in your Blog

2008-09-16T21:33:00.000-07:00

Ever wonder how the Store location of a super market displays the stores on a map with customized details? or the Branch Locator of Bank of America shows the Bank branches with full details?

Adding interactive maps to your blog can be very easy than you imagine - Google does all the underhood work for you :)

Step 1

1 - Login to Google Maps

2 - "Create new Map" - enter basic details

3 - Add locations to your new map

While adding the locations to the map you can select the image from the images that are available (or) you can upload your own icon.

Once the locations are added, the My Maps screen should display something like this image.

Step 2

1 - Login to map.google.com

2 - Click on My Maps and select the Map that you want to show in your blog

3 - When the map is open with the locations in the selected map

Click on "Link to this page" link located on Right top of the map. A popup window opens as in the image.

4 - Copy the HTML code snippet present in the "Paste HTML to embed in website" and paste inside your blog

5 - When you open/preview the blog, you should see the Google map embedded in your site as below.

Lets put a thought on the applications that are involved and the service orientered architecture concepts that went through in making this happen...

Whats new in Websphere Portal 6.1

2008-09-08T22:37:00.000-07:00

A Brief introduction to the new Websphere Portal 6.1 (beta).

IBM WebSphere Portal 6.1 Preview - What's New

View SlideShare presentation or Upload your own. (tags: ibm websphere)

My Analysis on Google Chrome

2008-09-07T10:16:00.000-07:00

Well to my surprise today,, the When I logged into Google Search Home page I saw the ad for "New! Download Chrome (BETA) - the new browser from Google" instead of the regular ad promoting the Mozilla firefox.

As a Google gadget fan, I downloaded the new browser immediately and found it is worth to download and use it.

On first look the browser

- Had a very light weight user interface giving more space for the site content instead of the toolbars, address bars and all.

- Google innivation can be seen at every inch of this browser, for example when you open the browser.

Instead of opening a blank screen, it opens up the frequently used site home page for you.

Effective use of the Title bar to show multiple tabs - saves space for user...

- The most striking point is its speed, it is lightening fast when compared to IE or Firefox on my system.

- Another noteworthy feature of this brand new browser is the "Task Manager".

- It can list all the sites that are currently open with in-depth technical details for nerds.

Well it is also equipped with a DOM inspector and a javascript debugger.. I am yet to explore these 2 features... Having said all this I cannot use this browser for my project activities as the tools that I use do not support these beta versions. (Documentum Web Publisher, HP Quality Center, etc.,).

Overall it is going to be a very useful browser and have all features to become a shining star in google sky. I am going to use this for my personal activities and surfing for sure.