Checkstyle is a static code analysis tool used to ensure Java source code complies with coding standards. It defines modules that check for code issues like naming conventions, line lengths, Javadoc comments, and duplicated code. Checkstyle runs from the command line or can integrate with IDEs. Originally created in 2001, it is now maintained by developers worldwide and supports Java 7 code.

1. Checkstyle
Stable release 7.5.1 / February 4, 2017
Repository github.com/checkstyle
/checkstyle (https://github.com/
checkstyle/checkstyle)
Written in Java
Operating system Cross-platform
Type Static code analysis
License Lesser GNU General Public
License
Website checkstyle.sourceforge.net (htt
p://checkstyle.sourceforge.net/)
Checkstyle
From Wikipedia, the free encyclopedia
Checkstyle[1] is a static code analysis tool used in software
development for checking if Java source code complies with
coding rules.
Contents
1 Advantages and limits
2 Examples of available modules
3 Usage
4 History
5 See also
6 References
7 External links
Advantages and limits
The programming style adopted by a software development project can help to comply with good programming
practices which improve the code quality, readability, re-usability, and reduce the cost of development. The
performed checks mainly limit themselves to the presentation and don't analyze content, and do not confirm the
correctness or completeness of the program. In practice, it can be tedious to comply with all the style
constraints, some of which could possibly harm the programming stages' dynamic; so, it may be useful to
determine which level of check is needed for a certain type of program.
Examples of available modules
Checkstyle defines a set of available modules, each of which provides rules checking with a configurable level
of strictness (mandatory, optional...). Each rule can raise notifications, warnings, and errors. For example,
checkstyle can examine:
Javadoc comments for classes, attributes and methods;
Naming conventions of attributes and methods;
Limit of the number of function parameters, line lengths;
Presence of mandatory headers;
The use of packets imports, of classes, of scope modifiers and of instructions blocks;
The spaces between some characters;
The good practices of class construction;
Duplicated code sections;[2]
Multiple complexity measurements, among which expressions.
Usage
Checkstyle is built in a JAR file which can run inside a Java VM or as an Apache Ant task. It can also integrate
into an IDE or other tools.
A Checkstyle plug-in can provide new functionalities, like:
overload syntax coloring or decorations in code editor;

2. decorate the project explorer to highlight problem-posing resources;
add warnings and errors outputs to the outputs.
Thus, the developer can directly access the code parts highlighted by Checkstyle.
History
Checkstyle, originally developed by Oliver Burn back in 2001, is maintained by a team of several developers
around the world.
The current stable release is version 5.7[3] which is targeted towards the Java 7 language.
See also
List of tools for static code analysis
EclipseCS (http://eclipse-cs.sourceforge.net/index.html) - Eclipse plugin for checkstyle.
SevNTU-Checkstyle (http://sevntu-checkstyle.github.com/sevntu.checkstyle/) - extension for EclipseCS
with number of check that are not part of checkstyle upstream.
Checkstyle for PHP (https://github.com/PHPCheckstyle/phpcheckstyle) - a PHP version of Checkstyle
References
1. "Checkstyle Home Page" (http://checkstyle.sourceforge.net/). 2010. Retrieved 2010-11-02.
2. "Checkstyle Duplicate Code Check" (http://checkstyle.sourceforge.net/config_duplicates.html). 2010. Retrieved
2010-11-02.
3. "Checkstyle Release Notes" (http://checkstyle.sourceforge.net/releasenotes.html). 2014. Retrieved 2014-06-29.
External links
Official website (http://checkstyle.sourceforge.net/)
checkstyle (https://github.com/checkstyle/checkstyle) on GitHub
Eclipse Checkstyle Tutorial (http://www.javatips.net/blog/2013/07/eclipse-checkstyle-tutorial)
Retrieved from "https://en.wikipedia.org/w/index.php?title=Checkstyle&oldid=767229189"
Categories: Static program analysis tools Java (programming language) libraries Java development tools
Software using the LGPL license Free software testing tools Software engineering stubs
This page was last edited on 24 February 2017, at 17:34.
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