Name is 30 characters on passport

I read the maximum length of characters is 30, is this correct? Do you remove the spaces for the name or is it okay to keep spaces in and have letters missing at the end?

Example for China Train Ticket pickup for 30 letters:

Say Surname: Smithsonian
Say First Name: Jonathan Quincy Adams

Would it be okay for: SmithsonianJonathanQuincyAdams with no spaces or is Smithsonian Jonathan Quincy Ad with letters missing at end okay? What would you write if it was greater than the maximum?