Hydrate is a Java mapping tool that lets you lay an object model over relational and XML data and move information quickly and efficiently between these three representations. Its strength lies in working with existing relational or XML database, over whose schemas you have little or no control, typically legacy or enterprise reference sources and data warehouses. Through Hydrate you can perform complex calculations and reporting that are best expressed in high-level problem domain modelling offered by an object-oriented language. It solves real-world problems in a practical way, is flexible, robust and has blistering performance.