XStream is a simple library to serialize objects to XML and back again. Features: Ease of use, no mappings, performance, clean XML, no modifications to classes, integration with XML libraries, full object graph support, customizable conversion strategies.

Jackson is a Java-based JSON-processing package that contains: * high-performance streaming JSON parser/generator * Tree Model that can be built from/written to parser/generator * Object Mapper that implements data binding to/from parser/generator API of streaming parser/generator is similar to Stax API used for efficient xml processing on Java platform. Beyond VERY fast Json parser and generator, Jackson project also offers full data binding support through 2 different approaches: "Object Mapper" for full POJO to/from Json data mapping (similar to JAXB2) and "Tree Mapper" for something similar to DOM and XPath.