Checkstyle Release Notes

Checkstyle 2

Release 2.4

New features:

Major refactoring on the way Checkstyle is configured. It is now completely based around properties. Big thanks to Vincent Massol for the suggestion on how to refactor the ANT task (bug 605141).
Check the package name against a pattern (request 597787). Patch provided by Simon Langford.
Detect the number of parameters in a declaration exceeding a specified amount (request 582144).
Inspired by patch 580410 from Shinya Ohnuma, now the error messages are localised.
Support checking to determine if an unused @throws exception is a subclass of java.lang.Error (request 583719).
Incorporate patch 555878 from Rick Giles to allow pattern for local final variables to be specified.
Incorporate patch 566855 from Rob Worth to optionally check that parenthesis are padded with spaces.
Incorporate patch 590931 from Vijay Aravamudhan to improve documentation of the build.xml file.
Incorporate patch from Vijay Aravamudhan to enforce requiring @version tag (request 543964).
Incorporate patch 607481 from Ville Skytt? to enforce wrap on operator at EOL.

Resolved bugs:

Incorporate a patch from Ronald Hastings (Boeing) to correctly handle C++ style comments being between Javadoc comments and declarations.

API changes (only relevant for IDE plugin authors):

New features:

Support checking to determine if an unused @throws exception is a subclass of java.lang.RuntimeException (request 540382).
Detect instantiations of classes that should not be instantiated (e.g. java.lang.Boolean) (request 550205).
Added ability to specify the base directory for reporting file names (request 571161).
Check for line wrapping on operators (request 553160).
Detect empty try blocks.
Detect empty catch blocks (request 516255).
Detect empty finally blocks.
Detect to-do comments (request 504275).
Detect use of lowercase l ("ell") in long integer literals.
Include column number in the XML output (request 555262).
Added ability to specify a properties file on the command line (request 557544).
Check for whitespace around "{" and "}" (request 557544).
Fix Javadoc errors under JDK 1.4 (request 568553).
Detect redundant abstract modifier in interfaces (request 573485).
Support running Checkstyle using the -jar option.

Resolved bugs:

API changes (only relevant for IDE plugin authors):

The get/setOutputStream methods have been removed from the AuditListener interface. The XMLLogger and DefaultLogger implementations now expect OutputStreams to be provided as a constructor argument.
The DefaultLogger now differentiates between info messages ("started checking file ...", etc.) and error messages (style errors found by checkstyle).

Resolved bugs:

The cache was not invalidated upon parameter change (Bug 522282).
Tabs were not counted correctly in line length checks (Bug 524671).
Problem when a Checker could not be created (Bug 528358).
The documentation of the command line property names did not list the property checkstyle.allow.tabs (Bug 529975).
The default regular expression for constant names allowed consecutive '_' characters to occur (Bug 540358).
Checkstyle reported unused @throws tag for multiple declarations of the same Exception. According to the Java BugParade this is incorrect, multiple @throws tags for the same exception are OK (Bug 540384).

New features:

added check for whitespace around '()'
added support for JDK 1.4 assert statements
added column number to error messages for better Emacs integration
added possibility to disable line-length checking by means of regular expressions
added possibility to disallow import of package hierarchies, e.g. sun.*
added failureProperty to ANT task
added check for 'public' modifier in interface method declarations, following the recommendation in chapter 9.4 of the Java Language Specification
added -r "dir" option to the commandline frontend, checkstyle will find all Java files contained in the specified directory
incorporated patch from Warner Onstine to configure the ANT task by means of a property file
added 'contrib' directory, contains XSL stylesheets for formating checkstyle's XML output (contributions by Ingmar Stein, Stephane Bailliez, Scott McCrory and Gray Herter)

New features:

added check for package.html
added flag allowPackage which acts similar as allowProtected
added support for ignoring multiple lines in the file header
added support for specifying the file header by means of regular expressions
added whitespace checks around '.', e.g. System . out . println()
added check for names of methods and local variables
check the order of modifiers (public, static, etc.) against the recommendation in the Java Language specification
added checks for curly braces placement
incorporated patch from Andrew Lang for more robust Javadoc parsing

Changes: