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Project API

This is the Jeka high-level API to build Java/JVM projects. API classes belong to dev.jeka.core.api.project package.

It introduces the concept of JkProject from where it performs compilation, testing, resources processing, packaging, publication, and more. JkProject is the root of a deep structure embracing the parent-chaining pattern for readability.

The API contains a lot of extension points to add specific behaviors.

Project Structure

JkProject structure
+- baseDir
+- outputDir
+- artifactLocator (define where artifact files are supposed to be created)
+- duplicateDependencyConflictStrategy
+- jvmTargetVersion
+- sourceEncoding
+- javaCompileToolChain
+- dependencyResolver
+- compilation  (produce individual binary files from production sources. This includes resource processing, code generation, processing on .class files, ...)
|  +- layout (where are located source and resource files)
|  +- source generators (plugin mechanism for generating source files)
|  +- dependencies   (stands for compile dependencies)
|  +- preCompileActions (including resources processing)
|  +- compileActions (including java sources compilation. Compilation for other languages can be added here)
|  +- postCompileActions
|  +- methods : resolveDependencies(), run()
+- testing
|  +- testCompilation (same as above 'prodcCompilation' but for test sources)
|  |  +- layout
|  |  +- dependencies (stands for test dependencies)
|  |  + ...
|  +- breakOnFailure (true/false)
|  +- skipped (true/false)
|  +- testProcessor
|  |  +- forkedProcess (configured the forked process who will run tests)
|  |  +- preActions
|  |  +- postActions
|  |  +- engineBehavior
|  |  |  +- testReportDir
|  |  |  +- progressDisplayer
|  |  |  +- launcherConfiguration (based on junit5 platform API)
|  |  +- testSelection
|  |  |  +- includePatterns
|  |  |  +- includeTags
|  +- method : run()
+- packaging (produces javadoc and source jar and bin jars)
|  +- javadocConfiguration
|  +- runtimeDependencies
|  +- manifest
|  +- fatJar (customize produced fat/uber jar if any)
|  +- methods : createJavadocJar(), createSourceJar(), createBinJar(), createFatJar(), resolveRuntimeDependencies()
+ methods :  toDependency(transitivity), getIdeSupport(), pack(), getDependenciesAsXml(), includeLocalAndTextDependencies()           

For convenience, JkProject provides a facade in order to make common settings friendly, without navigating deep into the structure. From facade, you can setup dependencies, java version, project layout, test behavior, test selection and publication.

   .configureCompileDependencies(deps -> deps
   .configureRuntimeDependencies(deps -> deps
   .configureTestDependencies(deps -> deps
   .addTestExcludeFilterSuffixedBy("IT", false)

If the fa├žade is not sufficient to set up the project build, you can use the main API. JkProject instances are highly configurable.

Here is a pretty complete example inspired from the Jeka Build Class .


Project dependencies are managed differently than in Maven/Gradle. Instead of defining a single collection of dependencies, each bounded for a specific scope/configuration, Jeka projects define 3 distinct classpaths : compile, runtime and test.

Each classpath defines its own set of dependencies independently, though they are defined relatively to each other.

Compile classpath : is defined using project.getCompilation().configureDependencies().

Runtime classpath : is defined from Compile Classpath. This base can be modified using project.packaging.configureDependencies().

Test classpath : is defined from a merge of Compile Classpath and Runtime Classpath. This base can be modified using project.getTesing().getCompilation().configureDependencies()

Full Text Description

An entire project dependency set can be declared with full text description.

By default, if a file named project-dependencies.txt is present in [PROJECT_DIR]/jeka, this content is taken in account to specify project dependencies.

Dependencies have to be declared with the format group:module:[classifier]:[type]:[version] where classifier, type and version' are optional.
See `JkCoordinate.of(String description)
for details.

To import bill-of-materials (aka BOM) just declare a dependency as 'group:module::pom:version'

Symbols @ and @@ can be used to mention dependency exclusions.


org.lwjgl:lwjgl-bom::pom:3.3.1   # Use lwjgl BOM so we don't need to specify lwjgl versions afterward
org.lwjgl:lwjgl:natives-linux::  # specify the 'natives-linux' classifier for lwjgl

- org.projectlombok:lombok       # remove lombok from runtime dependencies 

== TEST ==
@ org.apache.httpcomponents:httpclient  # exclude http-client from fluentlenium-junit transitive dependencies
@@ net.sourceforge.htmlunit:htmlunit    # exclude htmlunit from all transitive dependencies

Defines dependencies that will constitute the compile classpath.

Defines dependencies that will constitute the runtime classpath.
The dependencies will be the ones declared in the == COMPILE == section plus the ones declared in the == RUNTIME == section.
If dependencies declared in the == compile == section should not be included for the runtime classpath, they should be explicitly removed using the '-' symbol.

== TEST ==
Defines dependencies that will constitute the test classpath. The dependencies will be the ones declared in the == COMPILE == or == RUNTIME == sections (merge) plus the ones declared in the == TEST == section.


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