It would be good to provide more documentation for the test RunCodingRules.java.

I suggest a class-level comment of a paragraph or two explaining the conditions under which the test does something interesting and under which the test does a skip.

Something along the lines of:

/**
 * This is a test to verify specific coding standards for source code in the langtools repository.
 *
 * As such, it is not a standard unit, regression or functional test, and will
 * automatically skip if the langtools source code is not available.
 *
 * If the source code is available, it will find and compile the coding
 * style analyzers found in langtools/make/tools/crules/*.java, and run the resulting
 * code on all source files under langtools/src/share/classes. Any coding style
 * violations will cause the test to fail.
 */


If not already documented, the individual analyzers should have class-level comments
explaining their use as well.