Bug 149251 Inconsistent Handling of a Non-inheritable ROM Property
For a ROM property defined to be non-inheritable, an empty string property value should be consistently handled as an empty string, not as null. For example, an oda.dataSource extension defines a data source property with canInherit=false. When a oda-data-source handle get saved in a report design, it correctly includes the tag for such property, even when an empty string value is specified. <oda-data-source extensionID="my.oda.plugin" name="my Data Source" id="24"> ... <property name="ApplicationServer"></property> </oda-data-source> However, later when using the DE API to read its property value, a null is returned. Then when the report design is subsequently saved, the property tag is lost. Expects that an empty string value of a non-inhertiable property should be preserved.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/PropertySearchStrategy.java
*         is set.
	 */
	protected Object getSessionDefaultValue( Module module,
			ElementPropertyDefn prop )
	{
		if ( prop.isStyleProperty( ) )
		{
			
			return module.getSession( ).getDefaultValue( prop.getName( ) );
		}
		return null;
	}
	/**
	 * Tests if the property is inheritable in the context.
	 * 
	 * @param element
	 *            the element to test
	 * @param prop
	 *            definition of the property to test
	 * @return <code>true</code> if the property is inheritable in the
	 *         context, otherwise, <code>false</code>.
	 */
	protected boolean isInheritableProperty( DesignElement element,
			ElementPropertyDefn prop )
	{
		assert prop != null;
		return prop.canInherit( );
	}
}