I'd like to use the maven enforcer plugin to check to see if I have duplicate classes on my path. I've tried the example from here.
But when I run it like so:
mvn enforcer:enforce
I get this:
Failed to execute goal org.apache.maven.plugins:maven-enforcer-plugin:1.0.1:enforce (default-cli) on project datapopulator: The parameters 'rules' for goal org.apache.maven.plugins:maven-enforcer-plugin:1.0.1:enforce are missing or invalid
Is there a way to use this correctly?
EDIT #1
If changing my config to this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-enforcer-plugin</artifactId>
<version>1.0.1</version>
<executions>
<execution>
<id>enforce-versions</id>
<goals>
<goal>enforce</goal>
</goals>
<configuration>
<rules>
<AlwaysPass />
</rules>
<fail>true</fail>
</configuration>
</execution>
</executions>
</plugin>
Produces the same error.
The reason why your first version did not work is because there is a difference between a plug-in configuration inside the execution tag and a plug-in configuration outside the execution tag. The execution is only used when your plug-in is triggered by a special phase of the complete Maven build.
The Maven guide to configuration explains it better:
Configurations inside the tag differ from those that are outside in that they cannot be used from a direct command line invocation. Instead they are only applied when the lifecycle phase they are bound to are invoked. Alternatively, if you move a configuration section outside of the executions section, it will apply globally to all invocations of the plugin.