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/metadata/ElementDefn.java
if ( prop.isStyleProperty( ) && !isStyle )
				throw new MetaDataException(
						new String[]{name, prop.getName( )},
						MetaDataException.DESIGN_EXCEPTION_INVALID_STYLE_PROP_OPTION );
			
			prop.build( );
		}
	}
	/**
	 * Copies properties from the style onto this element. Note that the same
	 * definition object is referenced by both the style element and this
	 * element. That is, we copy the reference, not the data.
	 * <p>
	 * Containers are handled differently. Since the style system emulates CSS,
	 * containers can set all style property values, and the values cascade to
	 * the contents of the element.
	 * 
	 * @throws MetaDataException
	 *             if exception occurs when add style properties.
	 */
	private void addStyleProperties( ) throws MetaDataException
	{
		if ( !hasStyle( ) )
			return;
		if ( isContainer( ) )
		{
			
			
			List styleProperties = MetaDataDictionary.getInstance( ).getStyle( )
					.getLocalProperties( );