All contributions to HornetQ must follow the HornetQ code style.
If you're using eclipse then the eclipse project file in the root of the source tree will automatically have the code template set to the correct style. Doing auto format from inside eclipse will format your code according to the project style.
If you're using IntelliJ there is also an IntelliJ project file in the root of the source tree. Load that and the code style should conform to the project style.