Are you trying to integrate data from a REST web service with a data in your legacy RDBMS database? How about data from Excel or CSV file, JSON, XML, MongoDB contents? As Java developers we know how to read the data from these sources and how to stitch data together, all it takes some boilerplate code right? How about running some filters on that data, working with data type incompatibilities between data sources like converting a string type to decimal, doing aggregations like grouping the records by certain parameters and finally exposing it as REST service and you got 30 minutes do it? If you have NOT heard about Teiid (t-ee-d) before, this software is exactly what it is designed to do. It has many more features, but let's focus on Data Integration feature. One of the basic features of Teiid is to provide ways to integrate data from multiple disparate sources where it knows how to work with data type incompatibilities and provides a relational data engine that can plan a
Teiid is a Data Virtualization System for your Enterprise, convert the data you have to data you need!