Classycle: Analysing Tools for Java Class and Package Dependencies

Classycle's Dependency Checker searchs for unwanted class dependencies described in a dependency definition file. Dependency checking helps to monitor whether certain architectural constrains (e.g. in a layered architecture) are fulfilled or not.

For an Eclipse plugin see Alain Graf's ClassyclePlugin

Purpose and Features

Classycle does not need the Java source files because it analyses the compiled class files. Since version 1.3 it also evaluates Java Generics signatures.

From the analysis of the class files directed graphs of class and package dependencies are calculated. These graphs are further analysed in order to detect cyclic dependencies. For more details, see the User Guide Chapter 2. How Classycle works.

Classycle's Analyser produces a report (in XML) which contains

• the complete directed class/package graph
• all strong components of the class/package graph with more than one vertex (i.e. cycles of class/package dependencies)

Based on the class graph Classycle's Dependency Checker allows to search for unwanted dependencies between two sets of classes. An unwanted dependency between the start set and the end set can be either

• a direct one (a class of the start set uses a class of the end set) or
• an indirect one where a path goes via intermediate classes from a class of the start set to a class of the end set.

In addition the Dependency Checker can check the absence of large class cycles or package cycles.

Classycle tools can be run on the command line as well as an Ant task. Command line options and Ant task attributes are explained in the first chapter of the User Guide.

Release History

Classycle 1.4.2

Bug fixes:

• Java 8 lambda expressions are supported.

Classycle 1.4.1

New Features:

• In Classycle Ant tasks zipfilesets can be used. This feature is partially based on a patch by Tom Denley.

Bug fixes:

• Bug #3562457 fixed: Checking with 'dependentOnlyOn' printed expanded set definitions in the output. Now it prints only the set definitions as in the other check commands.

Classycle 1.4

New Features:

• New Dependency Checker command: dependentOnlyOn
• New renderer of dependency checking result: classycle.dependency.XMLResultRenderer
• New attribute reportFile of DependencyCheckingTask allows to write the dependency checking result into a file.

Classycle 1.3.3

New Features:

• The source of an analyzed classes and packages are added to the report.
• All zip/jar/war/ear files in folders are also analyzed.

Both features are based on a patch provided by Dietmar Wolz.

Classycle 1.3.2

Bug fixes:

• Bug #1892622 fixed: The bug appeared in the package dependency graph if a package contains external and internal classes.
  • Now a package classifies as an internal package if it contains at least one internal class.
  • An arc in the class graph from an internal class to an external class do not imply a corresponding arc between their packages if the package of the external class is an internal package.

Classycle 1.3.1

New Features:

• File attributes in ant tasks can also specify absolute paths. Thanks to Tim Vernum for the patch.

Classycle 1.3

New Features:

• Evaluates Java Generics signatures.
• Better syntax checking concerning miss-spelled keywords in dependency definition files.

Classycle 1.2

New Features:

• Merging inner classes: All inner classes vertices can be merged with their outer class vertex.
• New commands for the Dependency Checker:
  • Property definition and use
  • Checking sets
  • Checking absence of large class or package cycles

Classycle 1.1.1

New Features:

• XML report:
  • Date attribute in root element filled with current date.
  • Class/package element: Attribute cycle which denotes the cycle to which the class/package belongs.
• reportXMLtoHTML.xsl:
  • Sorts the cycles lists in accordance to their size.
  • Links to cycles for classes/packages belonging to a cycle.

Classycle 1.1

New Features:

• Ordinary string constants in Java code can be used as class references if they are valid fully-qualified class names and match certain patterns (see first chapter of the User Guide).
• Dependency Checker.

Documentation:

• Adapted to the new feature

Classycle 1.0

New Features:

• Ant Task ReportTask. Thanks to Boris Gruschko for its initial version!
• Many methods of class Analyser become public in order to be used by other Java classes (e.g. ReportTask).
• New command line option: -includingClasses and -excludingClasses (see first chapter of the User Guide).

Bugfixes:

• XML escaping of the title of the XML report

Documentation:

• Adapted to the new feature
• New with API documentation

Classycle 0.9999

New Features:

• Package dependencies and cycles
• Improved reportXMLtoHTML.xsl generates class/package links in popup windows.

Documentation:

• Adapted to the new feature

Classycle 0.999

New Features:

• Calculates and reports maximum fragmentation size for all classes of a cycle.

Documentation:

• Adapted to the new feature
• New chapter: Hints to improve design

Classycle 0.99

New Features:

• Reports layer index for all classes
• Improved reportXMLtoHTML.xsl

Bugfixes:

• Analysis of the constant pool

Documentation:

• New chapters of the User Guide explain how Classycle works and what it measures

Classycle 0.9