Spring Use new Java features (switch expressions, text blocks, new JDK methods)

Converted few cases where new switch statements/expressions make the code more readable. Few cases of multi line strings where converted to text blocks (unfortunately there is an issue of tabs/spaces because checkstyle doesn't know it is in textblock).

Also uses new methods to read strings directly.

Comment From: sbrannen

This has been merged into main in afb8a0d1b18b711f5c27a3662058372e2e3cbbee and slightly revised in 0415975dd1124d4c667fa4ef88e33c9701ff6f23 and a4956dfe26f61b7eb1daa2a4b8c688fa0cb7c644.

Thanks