StyleGuide

Hotspot Coding Style

How will my new code best fit in with the Hotspot code base? Here are some guidelines.

Why Care About Style?

Some programmers seem to have lexers and even C preprocessors installed directly behind their eyeballs. The rest of us require code that is not only functionally correct but also easy to read. More than that, since there is no one style for easy-to-read code, and since a mashup of many styles is just as confusing as no style at all, it is important for coders to be conscious of the many implicit stylistic choices that historically have gone into the Hotspot code base.

Nearly all of the guidelines mentioned below have many counter-examples in the Hotspot code base. Finding a counterexample is not sufficient justification for new code to follow the counterexample as a precedent, since readers of your code will rightfully expect your code to follow the greater bulk of precedents documented here. For more on counterexamples, see the section at the bottom of this page.

(TO DO: Import available Sun-internal docs!)

Whitespace

Naming

Grouping

Patterns

Counterexamples

Occasionally a guideline mentioned here may be just out of synch with the actual Hotspot code base. That's why we're using a wiki to document the guidelines. If you find that a guideline is consistently contradicted by a large number of counterexamples, please mention it here, to assist the rest of us coders with making an informed decision about coding style. The architectural rule, of course, is "When in Rome do as the Romans". Sometimes in the suburbs of Rome the rules are a little different; these differences can be pointed out here.

There may also be corrections needed. Please correct in a cautious and incremental fashion, because other Hotspot coders have been using these guidelines for years.