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/command/PropertyCommand.java
public void removeItem( ElementPropertyDefn prop, int posn )
			throws SemanticException
	{
		assert prop != null;
		
		assertExtendedElement( module, element, prop );
		checkListProperty( prop );
		List list = element.getListProperty( module, prop.getName( ) );
		if ( list == null )
			throw new PropertyValueException( element, prop.getName( ), null,
					PropertyValueException.DESIGN_EXCEPTION_ITEM_NOT_FOUND );
		if ( posn < 0 || posn >= list.size( ) )
			throw new IndexOutOfBoundsException(
					"Posn: " + posn + ", List Size: " + list.size( ) ); 
		Object obj = list.get( posn );
		doRemoveItem( prop, posn, obj );
	}
	/**
	 * Removes a value item from a simple value list.
	 * <ul>
	 * <li>The item must exist in the current effective value for the list.
	 * This means the list must be set on this element or a ancestor element.
	 * </li>
	 * <li>If the property is set on this element, then the item is simply
	 * removed.</li>
	 * <li>If the property is set on an ancestor element, then the inherited
	 * list is first <strong>copied </strong> into this element. Then, the copy
	 * of the target item is removed from the copy of the list.</li>
	 * </ul>
	 *