Renaming a dependency JAR before buiding a WAR in Maven

I was recently tasked with updating New Relic on our servers. When this was initially set up, the server was set up with a JVM command line option:

-javaagent:/usr/share/tomcat7/webapps/ROOT/WEB-INF/lib/newrelic-3.9.0.jar

When working on updating the version, I wanted to change this so that

1. We could update the New Relic Agent whenever a new update is available
2. We would not need to change the JVM command line each time the Agent was updated

To accomplish this, I wanted the New Relic Agent JAR name to always be the same, regardless of the version. I found maven-dependency-plugin through a web search, but ran across a problem where my WAR file was being created before the JAR was downloaded and renamed (using maven-war-plugin). All the examples I ran across used <phase>package</phase>, and while that looked right, I figured that this was still happening in the wrong life cycle phase for what I wanted to do. I resorted to reading the documentation, and with some experimenting found that <phase>prepare-package</phase> did this at the right part of the life cycle.
Here is the plugins section of the working pom.xml:
You do not need to include this dependency in your dependencies section, unless you are actually using it in your code.
We changed the server's JVM command line option to:

-javaagent:/usr/share/tomcat7/webapps/ROOT/WEB-INF/lib/newrelic.jar

And everything worked just great ... once I got the YAML file figured out 😉.

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Bonus Notes

• If you have not worked with YAML before, you will find out quickly that indentation is important to keep the hierarchy of properties right
• The newrelic.yml file included as an example in the newrelic-java.zip file appears to have an error in it. Specifically, the classloader_excludes property values need to be a commented list on the same line. I got parse errors using the example as-is (i.e., the list is indented with each item on a separate line, and has an extra comma at the end).
• If you are reading this and setting up a new configuration based on this article, you will also need the newrelic.yml file to end up in the same folder. To that end, place the file in /src/main/webapp/WEB-INF/lib in your Maven-based folder structure.