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
ArrayList inherited = (ArrayList) element.getProperty( module, prop );
		Object value = ModelUtil.copyValue( prop, inherited );
		
		PropertyRecord propRecord = new PropertyRecord( element, prop, value );
		getActivityStack( ).execute( propRecord );
		return;
	}
	/**
	 * 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>
	 * 
	 * @param prop
	 *            definition of the simple value list property
	 * @param posn
	 *            position of the item to be removed from the list.
	 * @throws SemanticException
	 *             if the item to remove is not found.
	 * @throws IndexOutOfBoundsException
	 *             if the given posn is out of range
	 *             <code>(index &lt; 0 || index &gt;= list.size())</code>.
	 */