I'm trying to inject a property into a java project when it is built by maven, by injecting the property via the command line, like 

```
mvn clean install -DMYPROP=myProperty  

```

I thought this was enough to have maven transform this into a System property, which could then be accessed in java via `System.getProperty("MYPROP")`. But this hasn't worked. 

So I did more research, one post here pointed to Maven Properties, so I tried the following, in the pom.xml: 

```
<properties>
    <MY.VARIABLE>${MYPROP}</MY.VARIABLE>
    <MY.ENV.VARIABLE>${env.MYPROP}</MY.ENV.VARIABLE>
</properties>

```

This is not working either. All the following properties are null

```
System.getProperty("MYPROP")
System.getProperty("MY.VARIABLE")
System.getProperty("MY.ENV.VARIABLE")

```

I've also tried using a properties-maven-plugin, based on [another question](https://stackoverflow.com/questions/3231797/specify-system-property-to-maven-project). That property was null as well.

Any suggestions?