Configuration

Core configuration sources

org.paramixel.core.Configuration exposes three entry points:

Map<String, String> classpath = Configuration.classpathProperties();
Map<String, String> system = Configuration.systemProperties();
Map<String, String> defaults = Configuration.defaultProperties();

All three methods return unmodifiable maps. Attempts to modify the returned map (such as put, remove, or clear) throw UnsupportedOperationException.

Class-loader resolution

Configuration loads paramixel.properties using the thread context class loader first. If the context class loader is unavailable (null) or cannot find the resource, it falls back to the defining class loader (Configuration.class.getClassLoader()). This ensures configuration is reliably located in containers, plugins, and test runners that set a restricted context class loader.

The same fallback strategy is used by Information to locate information.properties.

Configuration.defaultProperties() precedence

1. paramixel.properties from the classpath root
2. JVM system properties
3. built-in defaults

Built-in defaults currently add paramixel.parallelism when absent.

Built-in keys

paramixel.parallelism

Controls default runner parallelism. This key is used by both Runner (for thread pool sizing) and Resolver (for the parallelism of discovered Parallel roots).

paramixel.parallelism=8

Notes:

• Configuration.defaultProperties() sets it to Runtime.getRuntime().availableProcessors() when absent.
• Runner uses this value to size its thread pools and to detect potential nested-parallel deadlocks.
• Resolver uses this value as the parallelism for discovered Parallel roots when using Composition.PARALLEL. Overloads that accept a Map<String, String> configuration parameter let you control discovery parallelism explicitly.
• Individual Parallel actions can also set an explicit per-node limit with Parallel.of(name, parallelism, ...).

paramixel.failureOnSkip

Controls whether SKIP results are treated as failures for exit code purposes.

paramixel.failureOnSkip=true

Notes:

• Default is false. When false, SKIP produces exit code 0 (same as PASS). When true, SKIP produces exit code 1 (same as FAIL).
• This affects ConsoleRunner.runAndReturnExitCode(Action, Map), ConsoleRunner.runAndReturnExitCode(Selector, Map), and the Maven plugin.
• The no-configuration overloads (runAndReturnExitCode(Action) and runAndReturnExitCode(Selector)) always treat SKIP as success (exit code 0).
• In the Maven plugin, this corresponds to the <failureOnSkip> POM parameter or -Dparamixel.failureOnSkip=true system property.

Accessing configuration inside actions

Prefer Context#getConfiguration().

Direct.of("print config", context -> {
    String value = context.getConfiguration().get("my.custom.property");
});

paramixel.properties

Place the file on the runtime classpath, for example:

• src/test/resources/paramixel.properties for ordinary tests
• src/main/resources/paramixel.properties when examples live under src/main/java

Example:

paramixel.parallelism=4
my.custom.property=hello

System properties

System properties override file values.

./mvnw test -Dparamixel.parallelism=16

Programmatic runner configuration

Runner.Builder#configuration(Map<String, String>) overrides values from Configuration.defaultProperties().

Runner runner = Runner.builder()
        .configuration(Map.of("paramixel.parallelism", "6"))
        .build();

Programmatic discovery configuration

Resolver overloads that accept a Map<String, String> configuration parameter control the parallelism of discovered Parallel roots. When paramixel.parallelism is present in the map, that value is used; otherwise Configuration.defaultProperties() supplies the default.

Optional<Action> root = Resolver.resolveActions(
        Selector.byPackageName(MyTest.class),
        Map.of(Configuration.RUNNER_PARALLELISM, "4"));

Overloads that do not accept a configuration map use Configuration.defaultProperties().

Maven plugin configuration

The plugin accepts <properties> entries and also reads system properties.

Precedence in the plugin is:

1. Configuration.defaultProperties()
2. plugin <properties>
3. system properties whose keys start with paramixel.

The plugin passes configuration to discovery so that paramixel.parallelism controls both thread pool sizing and discovered action parallelism.

Example:

<configuration>
    <properties>
        <property>
            <key>paramixel.parallelism</key>
            <value>4</value>
        </property>
    </properties>
</configuration>

Plugin flags:

./mvnw test -Dparamixel.skipTests=true
./mvnw test -Dparamixel.failIfNoTests=false

paramixel.skipTests and paramixel.failIfNoTests are Maven plugin parameters, not core Configuration keys.