It could easily implemented if you overwrite the methods from the deparsers.

@jesperpedersen, on a side note, did you know about the Poor Man's SQL Formatter?

Pull requests are wellcome. As I mentioned the deparsers modifications should be easy.

An alternative to implementing this in JSqlParser will be to use Hibernate's implementation for SQL formatting. If you already have a dependency on the relevant libraries, just call:
String formattedSQL = new BasicFormatterImpl().format(sql);

Just implemented this: https://github.com/vertical-blank/sql-formatter

Extremely simple and effective.

An alternative to implementing this in JSqlParser will be to use Hibernate's implementation for SQL formatting. If you already have a dependency on the relevant libraries, just call:
String formattedSQL = new BasicFormatterImpl().format(sql);

I couldn't figure out the dependency. I tried hibernate-core but couldn't get the import correct.

@stewartbryson, I didn't try to import it directly from hibernate actually, as I needed to apply a few small changes to the hibernate formatter, so we just copied the source code of the file to our codebase, from:
https://github.com/hibernate/hibernate-orm/blob/master/hibernate-core/src/main/java/org/hibernate/engine/jdbc/internal/BasicFormatterImpl.java

Once I had that class, I can just import the class BasicFormatterImpl and call:
String formattedSQL = new BasicFormatterImpl().format(sql);