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Jeka contains a library for all regular things required to build/test/publish projects. The library does not depend on the execution engine and has zero dependency.

API Style

Jeka tries to stick with a consistent API design style.

  • All Jeka public classes/interfaces start with Jk. The reason for this is to ease distinction, in IDE, between classes supposed be used in productions or tests and the ones used for building. It also helps to explore Jeka API.
  • As a rule of thumb, Jeka favors immutable objects for shallow structures and mutable ojects for deeper structures. Both provide a fluent interface when possible.
  • In deep structures, final fields are declared public and have no getter counterpart.
  • All objects are instantiated using static factory methods. Every factory method name starts with of.
  • All accessor method names (methods returning a result without requiring IO, meaning computation only) start with get.
  • To create a subtly different object from an immutable one, Jeka provides :
    • Methods starting with with when a property is to be replaced by another.
    • Methods starting with and when a collection property is to be replaced by the same one plus an extra element.
    • Methods starting with minus when a collection property is to be replaced by the same one minus a specified element.
  • To modify a mutable object, Jeka provides :
    • Methods starting with set to replace a single property value with another.
    • Methods starting with add to add a value to a collection property.
    • Those methods return the object itself for chaining.

Domains Covered by the API

The previous example demonstrates how the Java/project API can be used to build and publish Java projects. This API relies on other lower level ones provided by Jeka. At a glance, these are the domains covered by the Jeka APIs :

  • Files : File trees, filters, zip, path sequence
  • System : Launching external process, Logging, Meta-info
  • Cryptography : PGP signer
  • Dependency management : Dependency management, publishing on repositories
  • Java : Compilation, javadoc, resource processor, manifest, packager, classloader, classpath, launching
  • Testing : Launching tests and get reports
  • Project : Project structure to be built
  • Tooling : Eclipse integration, intellij integration, Maven interaction, Git
  • Support : Set of utility class with static methods to handle low-level concerns