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javamavenpropertiesmaven-surefire-plugin

Setting properties via Maven command line

I'm confused about the correct way to set a property for some unit tests via the command line when using Maven. There are a number of questions (e.g. Specifying Maven memory parameter without setting MAVEN_OPTS environment variable, Is there a way to pass jvm args via command line to maven?, How to set JVM parameters for Junit Unit Tests?) that touch on this subject but none have the answer I'm looking for.

I want to set the property java.util.logging.config.class to some value but I don't want to set the MAVEN_OPTS environment variable.

I can configure the surefire plugin in my pom file with the property:

<argLine>-Djava.util.logging.config.class=someClass</argLine>

so that it is set every time the test phase is run.

However, if I remove the setting from the pom file and add the following to the command line:

mvn package -DargLine="java.util.logging.config.class=someClass"

then the following error in the test phase is reported and the build fails:

Error: Could not find or load main class java.util.logging.config.class=someClass

If I run the following from the command line:

mvn package -Djava.util.logging.config.class=someClass

then the following error is reported at the beginning of the build but the build and tests are successful:

Logging configuration class "someClass" failed java.lang.ClassNotFoundException: someClass

I don't really understand the behaviour. Can someone enlighten me?

Solution

  • Yes, you should have

    mvn package -DargLine="-Djava.util.logging.config.class=someClass"

    Notice the addition of -D inside the argLine.

    Let's explain why. argLine is indeed an attribute of the maven-surefire-plugin with the corresponding user property argLine. This means that you can set this property directly on the command line with -DargLine. But then, the value of that property is -Djava.util.logging.config.class=someClass. This is exactly what you had when you configured the plugin in the POM directly with 

    <argLine>-Djava.util.logging.config.class=someClass</argLine>

    Additionally, when you call

    mvn package -Djava.util.logging.config.class=someClass

    then you are not setting the argLine property. You are adding a system property.