Presentation Overview:

In this session users will take a deep dive at few cloud computing examples and participants will be able to know how to use cloud computing for Google App Engine and Amazon EC2.

The Google App Engine is a platform for developing and hosting web applications in Google-managed data centers. The Google App Engine is an example of cloud computing technology as it virtualizes applications across multiple servers and data centers. It is, at its heart, a powerful cloud computing platform designed to help you more easily create and manage scalable, JVM-based web applications. If you’re developing a Java application on App Engine you probably already know that you can use JPA and JDO Java persistence APIs to interact with the data store. Now learn how to take full advantage of these powerful APIs. We will explore few examples from Amazon EC2 like how to deploy groovy on grails application. We will also look at development tools to make your life easier while working with Amazon EC2, Amazon S3 and Simple db.

New : A picture is worth a thousand backlinks !!

Well to convey your story, try to use graphs , pictures or infographics.  Is this concept new  ?

Nope.

Illustrations have been always been very powerful.  But slowly with users creating cool info graphics, they have been catching more attention than plain text. For eg Look at the you tube flow chart below

Isn’t it cool ?

A useful link to create charts and infographics online. Some of them are free and others are paid.

http://www.1stwebdesigner.com/resources/free-online-tools-create-diagrams/

The link below is list of sites which are only into info graphics.

Omni graffe

http://www.omnigroup.com/products/omnigraffle/

Vector Designer

http://www.tweakersoft.com/vectordesigner/index.html

Free Mind mapping software

http://freemind.sourceforge.net/wiki/index.php/Main_Page

I tried http://www.onlinecharttool.com till now. Will update this post once I try out some more.

document.getElementById(‘buttonId’).disabled=true;

You may find that it will work in IE but on Firefox and Chrome.

Reason:

From W3Scholl,

“Enabled” Property isn’t standard property of XHTML 4(It’s Microsoft standard.).

So the solution would be to add this piece of code

var obj = document.getElementById(‘buttonId”);
getLabel = function(elem){
if (elem.id && elem.id==”label”) {
elem.id = “disabledLabel”;
}
};
Dom.getElementsBy(getLabel ,’td’, obj);

It is a beta exam which costs $50 and has 215 questions (oh my god!)

The exam topics are

1. The Servlet Technology Model
2. The Structure and Deployment of Web Applications
3. The Web Container Model
4. Session Management
5. Web Application Security
6. The JavaServer Pages (JSP) Technology Model
7. Building JSP Pages Using the Expression Language (EL)
8. Building JSP Pages Using Standard Actions
9. Building JSP Pages Using Tag Libraries
10. Building a Custom Tag Library
11. Java EE Patterns

You would find some helpful tests at Skill-guru to clear this certification. These tests are

Servlets and JSP interview questions

Design Patterns quiz

• The exam format and objectives for each of the exams will be the same as they were previously under Sun so there is no impact to those preparing to get certified.
• If you are currently holding a certification exam voucher for one of these exams, they will be valid through their expiration date and can be redeemed at Prometric.
• If you currently hold an existing Sun certification, your current Sun certification title will still be recognized under the Oracle certification program and will continue to be valid. You can upgrade your certification at any time to the latest technology release to receive an Oracle certification title.
• If you are in the process of preparing for a certification exam that you will take after September 1, 2010, you will receive an Oracle certification title and will have use of Oracle Certification Program Logo for endorsement of your proven skill by Oracle Corporation.
• Candidates taking exams between September 1-3 may see either Sun and/or Oracle-branded exam titles while registering and taking exams during this transition period.

More details can be found here

If you are looking for something popular , easy to use , low cost and working with distributed teams, you should go either with CVS or SVN.

Here is quick comparison of various VCS used . This is a result of survey done in 2008 by finalbuilder.

Soucre control surver

Looking at the results, you would surely go with SVN but one should look at why SVN is getting more popular and is taking over CVS.  SVN was created to fix some problems in CVS.  

Here are some major differences :

1. Repository basis

CVS is based on RCS files of versions control. Each file connected to CVS is an ordinary file containing some additional information. It is quite natural that the tree of these files repeats the file tree in the local directory. Thus, with CVS you should not be anxious about data loss, and you can easily correct RCS files if necessary.

The basis of SVN is a relational database (BerkleyDB) either set of binary files (FS_FS). On one hand, this settles many problems (for example, concurrent access through the file share) and enables new functionalities (for example, transactions at operations performance). However, on the other hand, data storage now is not transparent, or at least is not available for user interference. That is why the utilities for “curing” and “recovering” of the repository (database) are provided.

What does this mean ?

CVS repository files are rcs-format files that you can easily understand and manipulate with a text editor. SVN repository files appear to me to be opaque blobs. If the file system gets partially corrupted, you may well be better off with CVS.

2. Tracking history

CVS only tracks modification file by file while SVN tracks a whole commit as a new revision, which means that it is easier to follow the history of your project. Add the fact that all modern source control software use the concept of revision so it is far easier to migrate from SVN than it is from CVS

3. SVN supports versioning of binary files

4. SVN adds transactional commit (all or nothing)

5. Subversion doesn’t distinguish between file system space and “branch” space; branches and tags are ordinary directories within the filesystem.

In CVS, branches and tags are different things. A tag is a label for a revision. They are pretty useful for things like marking a RELASE tag for files to sync to your webserver.

Branches live in the same ‘namespace’ as the main file — it’s easy to track down all the mods of a particular file.

6.  Subversion can’t look at a file and tell you at what point someone created a branch or tag from it. Tools like CVSGraph can use this information to draw a tree of a file’s history. To do that with Subversion, you’d need to search all the branch/tags directories, and I haven’t seen any tools that do this well

7. You can move or rename files or directories cleanly in SVN

7. Commits are change sets on the whole tree (not just histories on individual files)

This post Subversion for CVS users can help to answer your questions

Here is another link in wiki comparing CVS and SVN.

Developers that are new to Hibernate constantly calling the saveOrUpdate method whenever a set of changes have been made to a POJO. This isn’t necessary. You only have to associate an instance with the Hibernate Session once within the scope of a transaction. From that point on, you can do whatever you want to your JavaBean instances. Hibernate will persist the final state of your instance when the current transaction is finally committed.

The following piece of code needlessly calls the saveOrUpdate method after instance variables have been updated. This is totally unnecessary, as the User instance was already associated with the Hibernate Session through the original call to saveOrUpdate.

hibernateSession.getTransaction();

User user = new User();

hibernateSession.saveOrUpdate(user);

user.setLoginName("skg");

user.setPassword("skg123");

hibernateSession.saveOrUpdate(user); /*Not recommended*/

hibernateSession.getTransaction().commit();

With the first call to saveOrUpdate, the instance named u becomes associated with the Hibernate session. From that point on, you can mess around with the user instance as much as you want, and Hibernate will take care of the persistence. You can initialize, update, change, and modify any instance variable of the user instance that you want, and Hibernate will save the final state of the instance once the transaction has been committed..

hibernateSession.getTransaction();

User user = new User();

hibernateSession.saveOrUpdate(user);

user.setLoginName("skg");

user.setPassword("skg123");

hibernateSession.getTransaction().commit();

skg

Dynamic queues and topics are created on-the-fly by applications using QueueSession.createQueue() and TopicSession.createTopic(). Dynamic queues and topics do not appear in the configuration files, and exist as long as there are messages or consumers on the destination. A client cannot use JNDI to lookup dynamic queues and topics.

The pre tags in IE 7 do wrap the text but the table width will remain wider and scrollbar appears, as if the text is taking full space. This problem doesn’t come in Firefox and Chrome. Can anyone help me out defining proper style for IE 7 for pre tags. for eg of you look at this code

<html>
 <style type="text/css">
<!--

pre {
 overflow:wrap;
width: 600px;
 white-space: pre-wrap;       /* css-3 */
 white-space: -moz-pre-wrap;  /* Mozilla, since 1999 */
 white-space: -pre-wrap;      /* Opera 4-6 */
 white-space: -o-pre-wrap;    /* Opera 7 */
 word-wrap: break-word;       /* Internet Explorer 5.5+ */
 display: block;
}
-->
</style>
<body>
<table width="70%" border="1">
 <tr> <td width="100%">
<pre> This is sample long text only to test IE 7 table width and it should be wrapping around but that does not happen . So we will have to find a solution </pte>
</td> </tr> </table>
</body>
</html>

You would not face this problem in Firefox or IE8.  It only happens with IE.

Solution : Use  table-layout: fixed;

If you apply the table-layout:fixed style for the inner table, where the data is in different columns, all columns get same area irrespective of their defined width.  But if applied it to the outer table, and it works fine.

Kindly take the test and give feedback.

There are New jersey driving test and Massachusetts dmv practice test available at Skill-guru