Sun Certified Developer for Java Web Services (SCDJWS) Certification Primer

This article was written for SCDJWS CX-310-220 Exam   
January, 2005

Web Services enable disparate systems to communicate with each other in a platform-independent way. Today, Information Technology increasingly needs to integrate various heterogeneous application systems, and one of the best ways to integrate them is by using Web Services.

Built on open standards like XML, SOAP, WSDL, and UDDI, Web Services technologies are widely adopted and are the best choice for Service Oriented Architecture (SOA). Many IT leaders are investing in Web Services and SOA, and these technologies are here to stay.

Having a certification in Web Services technologies will not only help you understand the nuts and bolts of Web Services, but can also improve your career prospects.

About the Exam

Prerequisites
The Sun Certified Developer for Java Web Services (SCDJWS) Certification requires you to be a Sun Certified Programmer for the Java platform (any edition), for appearing in the certification exam.

Objectives
The SCDJWS exam tests your knowledge on various aspects of Web Services, including core web service technologies, Java APIs to deal with those technologies, security, design and architecture of web services, and how web services fit into the J2EE Platform. You need to have a thorough understanding of the above to perform well in the exam.

Following are the objectives of the exam, as specified by Sun Microsystems:

  • XML Web Service Standards
  • SOAP 1.1 Web Service Standards
  • Describing and Publishing (WSDL and UDDI)
  • JAX-RPC
  • SOAP and XML Processing APIs (JAXP, JAXB, and SAAJ)
  • JAXR
  • J2EE Web Services
  • Security
  • Developing Web Services
  • General Design and Architecture
  • Endpoint Design and Architecture

 

 

For a detailed list of the objectives, click here.

Exam Type
The exam consists of the following question types:

  • Multiple Choice (this includes both, single response and multiple response)
  • Drag and Drop
  • Fill in the blank
The majority of questions are multiple-choice questions, with the number of correct choices to be chosen, clearly indicated.
You can expect a couple of drag-and-drop questions for this exam. Many of them would ask you to match between 2 lists of items. For example, a list of descriptions would be provided and you would be asked to drag and drop the appropriate Web Service technology/API responsible for fulfilling the given description.

Passing Score
The passing percentage for the exam is 68%, which boils down to 47 correct answers out of a total number of 69 questions.

Time Limit
The time allotted for the exam is 150 minutes, which is usually more than adequate.

Exam Fee
150 US Dollars.
How to Prepare?
To perform well in the exam, you must have at least a thorough understanding of Web Service technologies like XML, SOAP, WSDL, and UDDI. If you are a beginner, you can start by learning the basic concepts from books covering Web Services.

You can prepare for the exam in the following four phases. Each phase is equally important and the content of each phase has to be mastered to pass the exam with ease. You may want to prepare one phase after another because each phase consists of related technologies. All the phases together cover the entire exam objectives.

Phase 1: Core Web Service technologies and WS-I Basic Profile 1.0a
XML, XML-Schema, SOAP, WSDL, and UDDI, and consider the requirements imposed on these technologies by WS-I Basic Profile.  

Phase 2: Java APIs dealing with the core Web Service technologies like JAX-RPC, JAXP, JAXB, SAAJ, and JAXR.

Phase 3: Security: Various technologies related to securing Web Services An understanding of the various security mechanisms and security standards is required to answer the security related questions in the exam.

Security Mechanisms : Basic and mutual authentication, SSL, message level security, XML encryption, XML Digital Signature, federated identity, and trust.

Standards/Initiatives : Username Token Profile, SAML, XACML, XKMS, WS-Security, and the Liberty Project.

Phase 4: J2EE and Web Services
You need to understand how web services fit into the J2EE platform and how they can be used together with related J2EE technologies like Servlets and EJBs. In addition to this, you also need to understand how web services are designed and architected.

Preparation Time
The time it takes to prepare for the exam varies from person to person, based on their familiarity with Web Services.

For a Web Services novice, it could take about 40 days, spending 6 - 8 hours a day preparing for the certification exam.

For those who are familiar with Web Services basics, it could take about 20 days, spending 5 - 7 hours a day preparing for the certification exam.

For advanced users of Web Services, it could take about 10 days, spending around 4 hours a day preparing for the certification exam.

Tips and Tricks
Most of the Java/J2EE programmers are not very familiar with all the concepts of Web Services. So this exam would require a concrete preparation for performing well. This exam is not meant to be attempted half-heartedly. You need to be fairly confident and thorough with all the objectives before taking the exam.
  • The time available for the exam is generally sufficient. Try not to rush and take sufficient time to answer each question.
  • Be sure that you've memorized/are aware of all the restrictions imposed by WS-I Basic Profile 1.0a.
  • The exam has quite a few number of multiple choice - multiple response type of questions. Use the process of elimination in case you are not sure about the correct answer.
  • Remember to go through the 'Security' objective thoroughly as these concepts are relatively new to many people.
  • Practice correct code snippets for using APIs like JAX-RPC, JAXP, JAXR, JAXB, and especially SAAJ.
  • In JAXP, don't forget to read about XSLT, as there could be a couple of questions based on it, too.
Resources
Books
The books that are recommended for reference are: Training Courses
There is a training course recommended by Sun Microsystems for the SCDJWS Certification. To get more information on this course, click here.
Web Service Tutorials
The following links provide good tutorials on Web Services: Discussion Forums
Active participation in discussion forums also helps in the preparation to a great extent. Preparation Kits
Using exam simulators aids your exam preparation in many ways:
  • You can identify the areas you are weak in, so that you can focus more upon them.
  • Moreover, you can get a feel of the actual exam environment and the question types.
Whizlabs has launched the new SCDJWS exam simulator that ensures your success in the exam with its high-quality mock tests and quick revision tips. Check out the Whizlabs SCDJWS Exam Simulator.

Other Useful Resources
You can refer to the following links, which provide revision notes, tips, and other useful information for the exam: Summary
Web Services provide a simple, reliable, and platform-neutral way of communicating between diverse applications.

Web Services are here to stay as they are being built on open standards like XML, SOAP, WSDL, and UDDI. The exam focuses on knowing all these technologies and their usage to build Web Service applications.

Being a Sun Certified Developer for Java Web Services can really boost your knowledge, confidence, interest, and career prospects in this technology.

I wish you best of luck in your exam.  
About the Author
Kiran Baireddy is a graduate from Birla Institute of Technology and Science. His work experience of over 5 years includes software development and teaching in Java and related technologies. He holds SCJP, SCJD, SCWCD, SCBCD, SCDJWS, and other related IBM Certifications. He also conducts Instructor-led online trainings for the SCJP, SCWCD, and SCBCD exams for Whizlabs.