The encryption and decryption functionality was removed from version 9 of Community Commons after being deprecated in 8.7. The release notes say to use the functionality in the Encryption module from the Marketplace instead. Try the EncryptString and DecryptString actions from the Encryption module, you’ll find them in the “Private String – en/de-cryption” folder.
Good luck and I hope this helps.
Which ever module names you are getting the javaAction compilation errors try to update that modules from the marketplace it will resolve the issue may be the encryption module gives error because in the latest versions the encryption key is changed to 32bit from 16bit.