Preparing for Java Certification 7?

Changes to the exam process for Java certification 7, now require two exams to be cleared if not holding an older certification. Those who hold a prior certification, can take the Java SE 7 Upgrade Exam  and upgrade their quals.
The mantra to succeed in these certification exams appears to be 
(a) practice, practice, practice writing a lot of code without an IDE 
(b) Sit for mock exams. Enthuware appears to be a popular choice for Java 7 aspirants. 
(c) Follow a good book. Kathy and Sierra are to come out with their book for version 7, sometime late 2013, but if using their SCJP 6.0 guide, follow Bert Bates advice here and here.


 ** Links to Sample Tests **

• JavaRanch's collection of sample tests and sites that give a very good overview of the questions. This is the most comprehensive set of links and tests. A MUST!!
• Good set of questions based on SCJP 1.4 but well worth a study.
• JavaProgramming's  set of tests.

** Links to Study Notes and Materials **
• Study Notes  on AK Gupta's site. Also visit his compilation of links for MORE tests and resources.
• Another set of study notes on the exam. This one is based on SCJP 2.0 but it is still worth a look.
• Read a guy's experience and thoughts on how to prepare.

       ** Links to some good Java resources **

• Start with the JavaRanch and its forums.
• JavaWorld has a set of Java blogs and Q&A forums.
• JavaMagazine is Oracle's latest offering starting August 2011. 

Test Driven Development and a Code Kata

(Please click on the images to get a more readable version).

This week I thought of trying out a CodeKata problem and choose Kata 4 . The kata requires you to read a data file, parse it , extract some values and print the difference between them. A simple exercise one would say.

To explain the problem in brief. A data file containing the results of the football league is provided. The requirement is to extract the name of the team with the lowest goal difference in For and Against goal values. I decided to make this problem a bit more exciting by not just coding along a 'happy path' but also looking out for scenarios where there might be no valid data rows or there might be two teams matching the lowest goal difference criteria.

Using a test driven approach, I hacked out a set of basic JUnit tests to parse a valid data row and extract the For and Against goal values. My data row looked somewhat like this.

and the tests to extract the values from this data row looked like this:

Now that I was getting the For and Against Goal values, all I needed was to calculate their difference and store the team name (& goal difference) in a 'results list'. The tests for doing this were accomplished as below:

updateLowestGoalDifferenceTeam(). This function performs the core business processing in terms of updating the list holding the lowest goal difference team names. This function is given as below.