Sunday Sep 28, 2008
Thursday Aug 14, 2008
By manishkg on Aug 14, 2008
OpenPortal WSRP consumer has been integrated in Liferay trunk recently. RajeshT's blog is showing some screen shot of WSRP Consumer admin portlet deployed in Liferay portal. The steps for using WSRP Consumer admin portlets are described on WSRP wiki. We are currently working on admin portlet UI, so if you download Liferay trunk, you may find Consumer admin portlet look & feel different from what Rajesh's blog is showing. Rajesh has also shown WSRP category in "Add Application" under which remore portlets will be listed. Following the steps provided on this WSRP wiki page, I tried to access NetUnity's interop Producer URL. Here is the screenshot for NetUnity's portlet in Liferay.
Friday Jul 11, 2008
By manishkg on Jul 11, 2008
Coming back to the TSS article, the good point to note is that author has used OpenPortal portlet container to explore Portlet 2.0 features. If you are associated with Portlet technology since beginning, you might be knowing that Pluto used to be de-facto container for JSR 168 portlet development. But, after open sourcing of Sun's portlet container implementation and hosting it as sub project of OpenPortal at https://portlet-container.dev.java.net, it has gained lot of momentum. Here are the things that I like about OpenPortal portlet container:
1. Fully compliant JSR 286 implementation
2. Easy installation on Glassfish and Tomcat.
3. Easy deployment/un-deployment of Portlets
4. Good tooling support for Netbeans and Eclipse.
5. Last but not least, OpenSource and FREE :)
The author at TSS has provided link for download page of App Platform SDK, which is a GF + Portlet Container + WSRP bundle. If you already have Glassfish install, you can download Portlet Container 2.0 binary and deploy it on GF in secs. So, happy portlet writing.
Wednesday Sep 26, 2007
By manishkg on Sep 26, 2007
As I mentioned in my last entry, WSRP project is migrated from jax-rpc to jax-ws. What does that means for developers, is that you are no longer required to download jwsdp binaries and configure ExtenalDependencies.xml before build WSRP project. So, it is now a trivial task to download, build and deploy WSRP project with Portlet Container. Once you have deployed portlet container on Glassfish, you are only few steps away from deploying WSRP binaries. Here are these steps:
1. Download WSRP source code
svn checkout https://wsrp.dev.java.net/svn/wsrp/trunk wsrp --username guest) . Press enter when prompt for password
2. mvn package verify
3. cd dist
4. java -jar wsrp-configurator.jar <GLASSFISH_HOME> <GLASSFISH_DOMAIN_DIR>
5. Restart Glassfish
6. Access http://<host>:<port>/portletdriver
Let me know is you face any problem.
Tuesday Sep 11, 2007
By manishkg on Sep 11, 2007
Tuesday Aug 28, 2007
By manishkg on Aug 28, 2007
One of the major new feature added in the Portlet technology by the JSR 286 is the Portlet Filter. A portlet filter is a Java component that can be used to modify portlet request and response before/after any lifecycle method of the portlet is being executed. The concept of Portlet filter is same as that of servlet filter. The only difference is that a servlet has only one request handling method i.e. service() method and therefore there is only one type of the servlet filter. A portlet has four types of request handling methods and therefore there are 4 different types of portlet filters. The portlet API defines following interfaces for creating Portlet filter:
javax.portlet.filter.ResourceFilter (for serveResource method)
javax.portlet.filter.RenderFilter (for render method)
javax.portlet.filter.ActionFilter (for processAction method)
javax.portlet.filter.EventFilter (for processEvent method)
Each of the above filter interface contains a single doFilter(\*Request, \*Response, FilterChain chain) method which differs in the type of request and response object. For example, doFilter() method in ActionFilter takes ActionRequest and ActionResponse while doFilter() method of RenderFilter takes RenderRequest and RenderResponse objects. Each of the above filter interface extends a common base interface called javax.portlet.filter.PortletFilter. This common base interface contains init(javax.portlet.filter.FilterConfig filterConfig) and destroy() methods. The init(...) method makes sure that every Filter has access to a FilterConfig object from which it can obtain its initialization parameters, a reference to the PortletContext which it can use, for example, to load resources needed for filtering tasks. The init() and destroy() methods of a portlet filter are being called only once during their lifetime.
A single filter class can provide filter functionality for more than one lifecycle methods and also a single filter can provide filter functionality for more than one portlet. There can be multiple filter associated with one lifecycle method of a portlet. The javax.portlet.filter.FilterChain class (created by Portlet container) is used to invoke the sequence of filters applicable for a particular lifecycle method of a portlet. The doFilter() method of a portlet filter may create customized request and response objects by using \*RequestWrapper and \*ResponseWrapper classes and passing these wrappers to the doFilter() method of FilterChain.
In order to write a portlet filter, the developer is required to do the folowing 2 things :
1) Write a filter class - A filter class should implement one or more of the above mentioned four interfaces and should provide a no argument public constructor. The filter class is also required to override init() and destroy() method of javax.portlet.filter.PortletFilter interface.
2) Add entry of filter in portlet.xml - After writing a portlet filter class, it can be configured by adding following 2 xml fragements in portlet.xml.
<value>Filter 1 - portlet-container 2.0 Filter demo :)</value>
The first xml fragment defines a filter by providing a logical name to it. It tell portlet container about the filter class and the lifecycle phases supported by it. You can specify initialization parameters also.
The Second xml fragment specifies the portlet(s) for which this filter will be applicable. You can specify a single portlet name or mapping to a group of portlets using the ‘\*’ as a wildcard.
Saturday May 05, 2007
Friday May 04, 2007
By manishkg on May 04, 2007
Thursday Apr 26, 2007
By manishkg on Apr 26, 2007
A very nice introduction of Streaming API for XML is provided in this article. In summary, we can understand StAX by compairing it with SAX :
SAX (Simple API for XML) : Push API (observer design pattern... Parser feed the content of the document to the application as soon as they see it). Only reading of document is allowed.
StAX (Streaming API for XML) : Pull API (iterator design pattern... Client program asks the parser for the next piece of information ). Both read and write are possible.
There are many similarities in these 2 APIs -
Ease of Use, CPU and memory efficient, Forward only and No XPath capability.
Java Web Service tutorial is an excellent document to learn more about StAX.
Wednesday Apr 25, 2007
By manishkg on Apr 25, 2007
If you are using JAXB for XML to Java binding and geting javax.xml.bind.UnmarshalException: Unexpected element blah blah blah... the first thing you can do is to call setValidating(true) on Unmarshaller object. i.e.
JAXBContext jc = JAXBContext.newInstance("com.sun.java.xml.ns.portlet.portlet_app_2_0");
// create an Unmarshaller
Unmarshaller u = jc.createUnmarshaller();
This will help in getting little more details about the problem. For example, if your schema has declared <sequence> constraints on certain elements and your XML is not following it, the validation handler will report that certain tag name (element) is NOT allowed at this place and what all possible elements can appear after certain element.
One caveat here - setValidating() is a deprecated method and should be used only for debugging purpose.
Wednesday Apr 04, 2007
Monday Mar 26, 2007
By manishkg on Mar 26, 2007
Although Ruby on Rails framework bundles WEBrick webserver (100% written in Ruby) for developing/testing rails application, it is not the only web server that supports rails. Infact, a rails application can run on almost any webserver. The steps for running rails application using FastCGI module (bundles with the product) on Sun Java System Webserver 7 are mentioned in this article.
Read this, if you want to know what diferent deployment options people tried for rails applications. Here is another article that describes some benchmark results for various deployment configurations.
Friday Mar 23, 2007
Friday Mar 16, 2007