Please note that the latest version of Aspose.Words for Java i.e. 19.8 supports Open JDK 1.8. You can download Aspose.Words for Java 19.8 from the following link:
It should work but we do not recommend you use the old version of Aspose.Words for Java i.e. 18.7. Instead, please use the latest version i.e. 19.8.
P.S. Also, please note that we do not provide support for older released versions of Aspose.Words. We also do not provide any fixes or patches for old versions of Aspose APIs. All fixes and new features are always added into new versions of our APIs. So, please upgrade to the latest version i.e. 19.8. Hope, this helps.