EclipseLink/UserGuide/SDO/Introduction to EclipseLink SDO (ELUG)
This section introduces EclipseLink implementation of Service Data Objects (SDO) specification, as well as provides information on how you can use it in your application development.
- 1 Using SDO Metadata
- 2 Using Data
Using SDO Metadata
SDO Type acts similarly to a Class in Java, and provides much of the same metadata as the Java Reflection API provides for Java classes.
In EclipseLink, a Type wraps an object-XML mapping (OXM) descriptor.
Types can have supertypes, which corresponds to the EclipseLink concept of an inheritance policy (see ...).
What You May Need to Know About Open Sequenced Type
What You May Need to Know About DataObject Types for Data Types
SDO property acts similarly to a property in Java and provides much of the same metadata as the Java Reflection API provides for Java fields or methods.
In EclipseLink, a Property wraps an object-XML mapping in the following way:
- DataType=true + isMany=false (see OXM Direct Mapping (or an OXM Binary Mapping))
- DataType=true + isMany=true (see OXM Direct Collection Mapping (or an OXM Binary Collection Mapping))
- DataType=false + isMany=false + containment=true (see OXM Composite Object Mapping)
- DataType=false + isMany=true + containment=true (see OXM Composite Collection Mapping)
- DataType=false + isMany=false + containment=false (see OXM Reference Mapping)
- DataType=false + isMany=true + containment=false (see OXM Collection Reference Mapping)