JPOX-Spatial allows the use of JPOX as persistence layer for geospatial applications in an environment that supports the OGC SFA specification. It defines type mappings to let JPOX know how to persist a number of different Java geometry types (JTS, PostGIS-JDBC geometry types, Oracle's JGeometry). Thus a Java developer can mix spatial and non-spatial datatypes in his POJOs and can rely on JPOX to persist and query those types.
The mission for the JPOX Extension is to:
- Use of OGC Filter to produce a query against JPOX
- Expression evaulation against a POJO using JXPath
- Glue code for JPOX-Spatial Domains Models to be viewed as a simple POJODataStore
- Additional utility code to assist intergration between POJO domain model and GeoTools as required
How you can help?
- provide a test data set (and public database) with an interesting "complex" domain model
The following needs to be sorted out:
The following documentation is available (or at least intended):
Since most everything in the spatial world (pun intended) with OGC Filter - this is the first step. It will enable our Data Access and Rendering intergration.
Pojo Property Accessor
We need to make use of the Expression Improvements PropertyAccessor API to teach the filter system about working with Plain-Old-Java-Objects.
This can be done in two parts:
- simple reflection to access Bean properties (or reflection straight to Java fields?)
- full xpath support with JXPath (easy since beans + collections already supported)
This will allow the post processing filters to work.
Filter to JPOX Query Transformation
This work has been done for BBox query; we will need to go through the list.
See the separate wiki page for this: Data Access super class for DataStore
Given the above two the following is needed for rendering intergration:
- Teach PropertyAccessor the concept of "default geometry"
- Add getDefaultGeometry() to PropertyAccessor interface.
- Teach StreamingRenderer how to work with Content class rather then FeatureSource.
- Implement DataAccess and Source for JPOX