Custom PMD rules using XPath

Writing custom rules in PMD using XPath is an exciting concept, but unfortunately there are not many good tutorials or reference guides available on the internet for this.

Recently, we wanted to write custom PMD rules to extract Spring JDBC calls from the code base. We utilized the PMD desiger that is provided OOTB in Eclipse to easily write the rules.

Just open Eclipse -> Preferences -> PMD -> Rule Designer.
In Rule Designer, copy-paste your source code and check the AST (Abstract Syntax Tree) that is formed. You can also copy the AST XML from the menu bar and paste it on to a text editor. Writing the XPath expression then becomes very very simple !!!

For e.g. for finding our the Spring JDBC query calls the XPath was:
//PrimaryPrefix[Name[starts-with(@Image,'jdbcTemplate.query')]]

SONAR tool

My team has been evaluating the SONAR tool to manage code quality. I was impressed with the features and the user friendliness of the tool. SONAR can be used for both Java and .NET projects. It has a open plug-in architecture that allows any code quality tool to be plugged in.

For example, for static code analysis it combines the power of popular tools such as PMD, checkStyle and FindBugs into an unified user interface that is great to use :)

SONAR also has support for free code coverage tools such as JaCoCo.  Code coverage can be measured by unit tests or integration tests. You can even drill down to source code level - something I love to do :)

SONAR also integrates with new tools such as SQALE that have a formal approach for defining code quality in terms of maintainability, Testability, Reliability, Changeability, Efficiency, Security, Portability, Reusability, etc. Overall it is an invaluable tool to access Technical Debt.

Numega DevPartner Studio

Recently I installed DevPartner Studio and have explored the features provided by the tool. The tool integrates seamlessly into VS.NET and has the following high-level features:

- Static Analysis (Similar to FxCop or Code Analysis in VS Team Studio)

- Error Detection (You actually run the application/program and the tool would give a report of possible errors. This tool is more valuable in case of COM usage through .NET and in C, VC++ projects to detect OutOfBounds errors and dangling pointers, etc)

- Code Coverage (You run the application and at the end of it, a report is generated giving us code paths that were not executed. So helpful in finding dead code.)

- Memory Analysis (Heap analysis, shows object graph till root objects, no of objects created/destroyed etc.)

- Performance Analysis (E.g. U can create snapshots while running the application and the tool would give you the time spend in each method and many other stats. E.g. top 20 methods consuming most time, call graph, etc. Another cool feature is the source code window with time stats for each line on the left side. No more guessing what is taking so much time. )

- In Depth Performance Analyzer (CPU stats, Disk IO, Network IO, etc)

Visual Studio Team System provides us with many similar features. A VS product comparison can be found here.