Why won't my JSF app deploy to GlassFish?

Question

Yesterday I had trouble with my app suddenly failing to deploy from NetBeans to GlassFish server. I now know why, and am going to answer this question myself. I just wanted to record this information for the next person that needs it. I hope the etiquette of that is OK?

Symptom:

1. NetBeans would apparently build the project, not report any compile errors, and did show the following line in the output window: Building war: ...
2. but didn't deploy the app and didn't show the subsequent lines: --- maven-install-plugin:2.3.1:install ... -SNAPSHOT.war Installing ... -SNAPSHOT.war

What was the problem?

Answer 1

The problem was caused by a compile error in my code, which didn't show up until I did a complete "Clean and Build" ...and this couldn't be done until I shut-down the GlassFish server. Conclusion: If the problem occurs try shutting down the GlassFish server and doing a complete "Clean and Build".

Note: I actually first discovered the code error by trying to manually deploy the war using the GlassFish server console, so this is another thing to try.