Thanks for reaching out and I’m sorry for the troubles.
After looking into it, it seems that no JDK is pre-installed on our Windows images right now. We’ll update our documentation shortly. Sorry for the inconvenience.
I was able to install jdk8 and update the PATH environment variable accordingly by adding the following recipe in your .travis.yml file:
- choco install jdk8
- export PATH=$PATH:"/c/Program Files/Java/jdk1.8.0_191/bin"
- java -version
Could you try this out and let me know if it helps?
Thanks!