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<font size="2" face="Arial,Verdana,sans-serif"> <p>The next generation will take exams online by computer based software tools. One of the challenge in such online exam systems are scalability, ability to support more number of concurrent access. <strong>Skill Evaluation Lab</strong>, an advanced exam management system uses Java EE architecture for achieving high scalability and performance.&nbsp;</p> <h3>What is online exam?</h3> <p>Conducting exams on computer network without traditional paper style is called online exams. There will be one or more centralized server to store all exam data and each exam taker will be connected to this server by LAN/WAN or internet.</p> <h2>Challenge in conducting online exams</h2> <h3>Scalability:</h3> <p>This is the most critical non functional QoS we must consider to conduct online exams. I read many failure stories about online exam management systems which are got crashed when there is more load.</p> <h3>Performance:</h3> <p>This is another important non functional QoS for exam systems. What will happen if the system taking too long/failed to respond for taking exams. The system should perform same speed even when there are more concurrent access.</p> <h3>Security:</h3> <p>This very important for exam system where candidates can not access question papers/answers before writing exams. Each role will be allowed to perform based on permissions set. The security model should arrest all possible cheatings like multi login, view admin panels, view answers,etc.</p> <h3>Why Java EE?</h3> <p>Java Enterprise Edition platform is the proven architecture model which supports any kind scalability. With the help of server clustering and load balancing, any EJB centric designed Java EE architecture can scale and perform well for more concurrent users.</p> <h2>What is Skill Evaluation Lab?</h2> <p>This is an <a href="">Online Exam Software</a> developed by Java EE certified architect from world&#39;s best Java Certification exam software solution vendor. They are not only expert in Java technology and also have enough knowledge in exam software solutions. Their exam solutions reached all over the world (around 150+ countries). You can find tons of articles and videos about this product by searching &quot;Skill Evaluation Lab&quot; keyword on web.&nbsp;</p> <h3>Where it can be used?</h3> <p>The answer is simple, anywhere. It can suit into any kind of organization such as IT Organizations for employment testing and training, Recruitment Agencies for employment exams, Training Companies for practice exams, Universities for practice exams or conducting real exams with world&#39;s first web pen mouse writing solution, Government Organizations for conducting exams and Schools/Colleges for practice exams.</p> <h3>Scalability proved package</h3> <p>The application has been tested with many load testing tools and also tested on client&#39;s environment with more than 2000 concurrent access on single server node with just 3GB RAM.</p> <h2>Features of Skill Evaluation Lab</h2> <p>You can watch this youtube video to know the features. <a href=""></a></p> <ul> <li>Role based access to match with real-life users for colleges or schools.</li> <li>User management with grouping hierarchy. So that we can generate reports under group level for ranking or appreciation.</li> <li>Test and Question Management can be done by XL sheet or from web editors.</li> <li>Question can have images, flash files, video, audio or any attachments.</li> <li>Exam manager can create voice questions by recording their voice on desktop phone.&nbsp;</li> <li>Multi-language support to create questions in any language.&nbsp;</li> <li>The product will evaluate and generate results instantly.&nbsp;</li> <li>Answer evaluation for pen writing or descriptive type can be done manually by user friendly evaluation screens.&nbsp;</li> <li>An instant communication alerts for all test events by email or SMS.&nbsp;</li> <li>Test Monitor to view current test event status.&nbsp;</li> <li>Improve organization/college/school skill levels by Test/topic comparison charts by measuring overall weakness areas.</li> </ul> <h2>Technology and Environment</h2> <p>The product can be deployed on local or remote server. 100% open source platform and no commercial license required for running this application. The product requires Java EE 4 or above enabled JBoss application server and MySQL database.&nbsp;</p> <h2>Benefits of Skill Evaluation Lab for corporates:</h2> <h3>Employment Test:</h3> <p>Measure and shortlist candidates based on actual skills by Skill Evaluation Lab exams instead of blind-doctored resumes</p> <h3>Employment Training:</h3> <p>Create practice or quiz exams to improve knowledge in specific skills that are required for your employees. Easy to differentiate employee skill levels for different assignments.&nbsp;</p> <h2>Benefits of Skill Evaluation Lab for education sectors:</h2> <h3>University or School Tests:&nbsp;</h3> <p>Cut-down your training cost by Skill Evaluation Lab practice exams. Move from traditional paper based exams to next generation computer based exams. Track candidates/faculties skill level and improve.</p> <h3>What is next?</h3> <p>Go to this vendor site trial at <a href=""></a> and take test drive. Contact them and get the software package for your company/college/school and enjoy making online exams. Thanks for listening my article, hope you can conduct online exam by using this software.&nbsp; <strong>Cheers !</strong></p> </font >
<font size="3">The latest Java EE 6 Certification for business component developer is divided into two certifications - EJB and JPA. These two certifications are completely different from previous <font face="georgia, serif">SCBCD</font>/<font face="georgia, serif">OCPJBCD </font>certification.<br> <br> The Java Designer’s general principle to architecting high scale or low scale application is choosing between <font face="georgia, serif">EJB Centric Design</font> (with EJB) or <font face="georgia, serif">Web Centric Design</font> (without EJB). <font face="georgia, serif">OCE EJB Certification</font> covers all design/developer knowledge required to implement Enterprise Java Bean Components.<br> <br> <b><font face="georgia, serif">Difference between SCBCD 5 and OCE EJB Certification</font></b><br> Oracle Certified Professional, <b>Java EE 5 Business Component Developer</b> (<font face="georgia, serif">Formerly<b>:</b></font> <font face="georgia, serif"><i>Sun Certified Business Component Developer</i></font> (<b>SCBCD</b>)) certification provides knowledge required to develop Java EE 5 EJB and JPA applications. However, OCE EJB only covers Java EE 6 EJB components and OCE JPA covers only Java EE 6 JPA API.<br> <br> SCBCD 5 = Java EE 5 EJB + Java EE 5 JPA<br> OCE EJB = Java EE 6 EJB<br> OCE JPA = Java EE 6 JPA<br> <br> Oracle introduced new level (Expert) for these certifications instead of regular professional level.<br> <br> You can find complete info about OCE EJB certification from this article.<br> <a href=""></a><br> <br> <b>How OCE EJB exam improves your JEE 6 Design Skills?</b><br> The certification tests your design decision knowledge about choosing right EJB for the given business problem. Note that, Java EE Architect exam has similar type of questions to test architecture knowledge in business tier components. <a href="">EJB certification</a> is more focused on design and development of Stateless Session Bean, Stateful Session Bean, Singleton Session Bean and Message Driven Beans. <br> <br> The exam may not cover questions about web services and it is beyond EJB certification topics, however it is covered on architecture and web services exams.<br> <br> <b><font face="georgia, serif">Introduction to Java EE 6 EJB Types</font></b><br> Java EE 6 provides the following EJB components. <ol><li>Stateful Session Bean</li> <li>Stateless Session Bean</li> <li>Singleton Session Bean (<font face="georgia, serif"><i>new bean introduced in Java EE 6</i></font>)</li> <li>Message Driven Bean</li> </ol> The exam will tests your applicability knowledge of these components in different business scenarios. You may also need to have thorough knowledge in annotations to develop these <i>EJB components</i> with timer services, interceptor methods, transactions and security.<br> <br> Note that Singleton bean is under session type introduced in Java EE 6.<br> <br> <b><font face="georgia, serif">EJB Design decision</font></b><br> <font face="arial, sans-serif">1. </font><b>Using Stateless Session Beans</b><br> You are developing a business component where it does not contain the data for a specific client. Your search component is the best example for this scenario. Note that search requires only one method invocation with search query among all the clients to perform the generic task (executing search query on server side). <br> <font face="georgia, serif">Example</font>: Google search, Yahoo search and MSN search. <br> <br> <i>The following contents are taken from Oracle:</i><br> <b> When to use Stateful Session Bean:</b><br> <ul><li>If the bean does not contain the data for a specific client.</li> <li>If there is only one method invocation among all the clients to perform the generic task.</li></ul> <span style="font-family:arial,sans-serif">2.&nbsp;</span><b>Using Stateful Session Beans</b><br> You are developing a business component where it wants to hold information about the client across method invocation. The most common example ofthis type of implementation would be “Shopping Cart”, where it needs to hold client specific information.<br> <br> <font face="georgia, serif">Example</font>: Gmail, Yahoo Mail and Facebook.<br> <br> <i>The following contents are taken from Oracle:</i><br> <b> When to use Stateful Session Bean:</b><br> <ul><li>What the bean wants to hold information about the client across method invocation.</li> <li>When the bean works as the mediator between the client and the other component of the application.</li> <li>When the bean have to manage the workflow of several other enterprise beans.</li></ul> <span style="font-family:arial,sans-serif">3.&nbsp;</span><b>Using Singleton Session Beans</b><br> You can easily decide by the name itself, when you want to have exactly one instance of a session bean go for Singleton session bean. You are developing an application where you want to have some configuration parameters needs to be used across different modules and they needs to be available during your server startup. You can easily implement this scenario by using Singleton Session bean.<br> <br> <i>The following contents are taken from Oracle:</i><br> <b> When to use Singleton Session Bean</b>:<br> <ul><li>State needs to be shared across the application.</li> <li>A single enterprise bean needs to be accessed by multiple threads concurrently.</li> <li>The application needs an enterprise bean to perform tasks upon application startup and shutdown.</li> <li>The bean implements a web service.</li></ul> <span style="font-family:arial,sans-serif">4.&nbsp;</span><b>Using Message Driven Beans</b><br> Unless like regular Java method calls, MDBs are called asynchronously without blocking. Note that Java EE 6 Session beans allow you to send JMS messages and to receive them synchronously but not asynchronously. To avoid tying up server resources, do not to use blocking synchronous receives in a server-side component; in general, JMS messages should not be sent or received synchronously. To receive messages asynchronously, we should use a message-driven bean.<br> <br> <b>The certification tests coding/design knowledge in the following areas:</b><br> <ul><li>Java EE design choices about using different EJB components.</li> <li>Implementing Session Beans with annotations.</li> <li>How to access Session Beans from other components or clients.</li> <li>Implementing Singleton Session Bean</li> <li>The exam requires knowledge in developing Java EE Applications Using Messaging and Message-Driven Beans.</li> <li>Using Timer Services in EJB components.</li> <li>The other topics you must have good knowledge are Interceptor Classes and Methods, Transactions and Security.</li></ul> <b>What is next?</b><br> Go and register for OCE EJB exam from Oracle. <br> Prepare for your exam with good EJB Study materials like Java EE 6 EJB OCE Training Lab.<br> Take exam and achieve your potential certification.<br> Cheers !!!<br> <br> <b>Reference</b>:<br> <a href=""></a><br> <a href=""></a></font>
In this Article I will explore the barcode concepts and market requirements from Java SE/EE and ME editions, by an introduction explaining the main idea behind the barcode API along with the main concepts and demonstrate how the barcode engine migration is done from older version to new one powered by Java 7 NIO.2 API as well as Java 7 language features. Moving to the implementation by introducing the software pre-requisites, then providing an example with implementation steps on how it's implemented, followed by explanation of the example working mechanism with running demo, then providing the references and finally development tips.