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javamavenmaven-plugin

Set maven property from plugin


I've read some questions here about how to set a property (most of them talked about the version number for an application) from a maven plugin. It seems there's no easy way of doing this and the best solution I found is to have a filter.properties file which is updated from the plugin and used by the main pom file to filter the desired resources.

I tried another solution after I read this from the Maven documentation (Maven filter plugin):

Variables can be included in your resources. These variables, denoted by the ${...} delimiters, can come from the system properties, your project properties, from your filter resources and from the command line.

I found interesting that variabled can be read from system properties. So, I modified my plugin to set a system property like this:

System.setProperty("currentVersion", appCurrentVersion);

However, filtered resources don't seem to read this value. Could anybody tell me what's wrong with this approach?

UPDATE: I'm running my plugin in the validate phase.

Thanks a lot.


Solution

  • Don't set it as System Property, set it as Maven Project property

    // inject the project
    @Parameter(defaultValue = "${project}")
    private org.apache.maven.project.MavenProject project;
    
    // and in execute(), use it:
    project.getProperties().setProperty("currentVersion", appCurrentVersion);
    

    See:


    An edit suggested using Properties.put() instead of Properties.setProperty(). While technically, Properties implements Map, this usage is discouraged explicitly in the Properties javadoc.