Server Side Validation in Web Apps

I took a long break and now back again with Active blogging. Its good to be back.
This time I am discussing the importance of server side validation. I observed many of merchant's sites has a client side validation usually using JavaScripts , after validating the data like if the Integer's value is within some bounds ,it does not get validated again on server which can cause a huge error while making transactions on the server , As Javascript validation can be manupulated any time on the client, here is link which shows how easy it is to modify the validation using Javascript. Without validating data again on server and processing it can break the system easily. Java script validation should only be used to avoid round trip to the server nothing beyond that and data should again be validated on the server.

Google Developer's Day Videos.

I was just going through the Google developer's day video's on Youtube .
I found it interesting.

You can watch it here

Java Cryptography

Cryptography is about securing your data during communication. Java JDK has inbuilt APIs called JCE that helps you to implement the various cryptography methodologies.

I found the following articles on the web which very well explains the implementing Cryptography in java.

Part I - Explains the cryptography concepts.
Part II - More details with java code examples.

Four Golden reasons to use O-R Mapping frameworks

O-R mapping frameworks(Toplink from Oracle,JDO from sun, Hibernate from Open source community) are around for quite long period of time. These lightweight frameworks simplify the development of persistence layer in a J2EE applications. I filtered down to four golden reasons for using O-R mapping frameworks for any J2EE applications.

• Portability across databases
• Support for Transaction management
• Business logic can be unit tested without deploying it to the container
• These objects can be directly consumed by the presentation layer without writing the additional DTO(Data Transfer objects).

The O-R mapping persistence layer can be easily migrated to almost any database by just changing the descriptor file. The benefit of using O-R mapping tools over EJB 2 is that , its not required to be deployed on container for unit testing of your business logic, moreover these objects can be used by the presentation layer for the presenting the data which avoids need of additional DTO objects.

There is good article on javaworld about J2EE design decisions which very well explains the importance of O-R mapping frameworks.

Google Web-toolkit - The Future desktop web applications

With the released of Google Web-toolkit(Open Source Soft,beta release) , developing AJAX based web applications became lot more easier for the java developers. With the help of Google web toolkit , the entire application can be written in Java (similar to awt coding std) which gets converted into the web application using Web-toolkit compiler. We can easily plug in the Spring Framework environment into the GWT application, in that way we can go with the J2EE based framework development. Google web toolkit provides you the two ways of running your application. One in the hosted mode and other is in the web mode . The basic difference in these mode is that in hosted mode your java code gets converted into Javascript-Html code every time when you run your application and in the web mode(production mode) it picks up from the cached html. AJAX code generated in such a way that it runs on all the browsers which is amazing ...

I think Google web toolkit is going to be the future for desktop web applications. Now we can provide a desktop based functionality on web very easily without writing the single line of AJAX specific code. For the server side coding , we can very easily use O-R mapping tools(EJBs,Hibernate,Oracle Toplink) . Google Toolkit provides you to write server side code in the specially written class which extends RemoteServiceServlet class which is similar to a servlet. It also provides a way to serialize a java object between the client and server which gets converted into an ajax call to a servlet after compilation.

Google Toolkit provides you AWT equivalent components called Widgets for creating the basic UI in html pages. Some of the widgets like popups,menues,tabs are just amazing. There are number of open source widgets available from the GWT community which is growing with every passing day. Its surly a future tool for j2ee application development , thanks to Google for this innovative tool.