We needed a simple tool which would allow us to replace values of environment variables in files and would work as a Java library and as a command line tool.
Apache Velocity is a mature and reliable Java template engine which we chose as the basis for this small utility.
After checkout, build it with maven:
mvn clean install
You can run it with following command inside the project root folder:
java -jar target/velocity-renderer-standalone.jar -s ./src/test/resources -f .*.vm -d ./target
After that you can see the rendered file at target/sample.test:
cat target/sample.test
To see the template, from which sample.test was generated:
cat src/test/resources/sample.test.vm