8.7. Summary

The string and wrapper classes in Objective-C aren't conceptually much different than those in Java. The wrapper classes are more generic and can wrap more than just the built-in value types. Unlike Java, Objective-C strings can be subclassed. This means that they might be mutable, but generally aren't, and can usually be treated the same way they are in Java. Remember to use %@ instead of %s in format strings, and use the NSFormatter classes for sophisticated value conversion.