Represents the fundamental data structures of the Design Engine.

## Package Specification

The core package represents the key data structures of the design engine. Other packages build on these classes to offer the elements, properties, structures, slots and other concepts defined in the Report Object Model.

The key classes in this package include:

- {@link org.eclipse.birt.report.model.core.DesignElement} is the base class for all report elements. See the extensive documentation in this class for information about the services common to all report elements.
- {@link org.eclipse.birt.report.model.core.IStructure} and {@link org.eclipse.birt.report.model.core.IPropertySet} provide generic access to class members and element properties respectively.
- {@link org.eclipse.birt.report.model.core.ContainerSlot}, {@link org.eclipse.birt.report.model.core.SingleElementSlot}, and {@link org.eclipse.birt.report.model.core.MultiElementSlot} implement the slot-based containment relationships between elements.
- {@link org.eclipse.birt.report.model.core.NameSpace} implements an element name space.
- {@link org.eclipse.birt.report.model.core.StyleElement} and {@link org.eclipse.birt.report.model.core.StyledElement} implement the style system.