mjstrasser / janos

Java Annotation extension for Apache Olingo V2

Janos - Java Annotation extension for Apache Olingo V2

This extension provides Java Annotations for defining the OData (V2) EDM and Interfaces (Hooks) for attaching generic data sources providing the data. The extension is based (forked) from the Apache Olingo Annotation Processor (see Olingo Homepage and Maven Central).

Current Features (for stable version)

• Create your EDM (Entity Data Model) with using Java Annotations (the EDM-(Java)-Annotations from the Apache Olingo OData Library (v2) (or in maven central))
• Data Access Layer with...
  • ...DataSource for providing the Data from the view of an OData Service
  • ...DataStore for providing the Data from the view of an Data Storage Service (e.g. a Database)
• Generic DataSource and DataStore implementations for...
  • ...using the EDM-(Java)-Annotations in combination with an In-Memory-Store (none-persistent)
  • ...using the EDM-(Java)-Annotations in combination with an JPA-Based-Store
• ReadOptions and ReadResult for optimized data access (read) in the DataStore layer

New and Noteworthy

• Version 2.3/3.0 (current development version - release upcoming)
  • Planned: Implement enhancement in [Janos#10]: More customization over generic (default) data processing (see also in Roadmap at the end of this readme)
• Version 2.2 (current development version - release 21.02.2016)
  • Janos#9: Add method to create an EdmProvider based on Annotations (accordingly annotated classes)
  • Janos#8: All fields of an POJO are handled as @EdmProperty by default (if no fields with annotations (beside @EdmKey) is found)
  • Updated Apache Olingo to version 2.0.6 and because Olingo updated to GSon 2.4 also updated Gson.
  • Switch to real Semantic Versioning. Based on this decision it is possible that next version will be 3 .0 instead of 2.2, however the API did not changed, hence the release version is now 2.2.0.
• Version 2.1 (current stable version - released 07.10.2015)
  • Added ReadOptions and ReadResult for optimization of data access (read) in the DataStore layer
  • Refactored API packages (incompatible changes to 2.0)
  • Refactored (changed) API methods
    • org.apache.olingo.odata2.janos.processor.api.data.source.DataSource createData(...) method now returns the new created instance instead of modifying the given data parameter instance.
    • org.apache.olingo.odata2.janos.processor.api.data.store.DataStore all data access methods can now throw a DataStoreException
  • Updated to newest Apache Olingo version 2.0.5
• Version 2.0 (released 03.09.2015)
  • Made DataStore and DataSource part of the public API
  • Provide a generic JpaAnnotationDataStore and a DualDataStoreManager which can handle Model classes with JPA annotations
  • Added support for FunctionImports via the @EdmFunctionImport annotation and the FunctionExecutor interface
  • First stable version based on fork of the Apache Olingo Annotation Processor (see Olingo Homepage and Maven Central).

Roadmap

• Abstract Topics
  • Provide more Extension points for customization of generic (default) data processing (e.g. start/end of transaction). Beside the actual only possibility to use the ReadOptions and ReadResult for performance optimization. -> created enhancement Janos#10
  • Provide more documentation (e.g. tutorials) as just the source code
• Specific enhancements
  • Support ReadOptions and ReadResult for FunctionSource (FunctionImports)