Introduction - If you have any usage issues, please Google them yourself
XStream is a simple library to serialize objects to XML and back again.
If using the enhanced mode, XStream can re-instantiate classes that do not have a default constructor. However, if using a different JVM like an old JRockit version, a JDK 1.4 or you have restrictions because of a SecurityManager, a default constructor is required.
The enhanced mode is also necessary to restore final fields for any JDK < 1.5. This implies deserialization of instances of an inner class.
Auto-detection of annotations may cause race conditions. Preprocessing annotations is safe though.