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
* set of contents is called a <em>slot</em>. Each slot has a cardinality
 * (one or many), and a type. More specifically, each slot can contain a set of
 * element types. The {@link SlotDefn}class holds details of a slot.
 * <p>
 * Slots are indexed using a slot ID. The ID is a zero-based index, allowing the
 * caller to easily iterate over the slots.
 * 
 * <h3>Names and Name Spaces</h3>
 * 
 * Elements can have a name. Some elements require a name, for some the name is
 * optional.
 * <p>
 * The element name is meant to be unique within a <em>name space</em>. Name
 * spaces reside on the root element. Name spaces include elements, styles, data
 * sources, data sets and so on. Each element type identifies its name space
 * using a name space ID.
 * 
 * <h3>Method</h3>
 * 
 * Elements can have methods that defines the script. All methods are defined in
 * metadata. The element can inherit the methods defined in parent. Property
 * mask can change the method visibility.
 */
public class ElementDefn extends ObjectDefn implements IElementDefn
{
	/**
	 * The property is hidden in the property sheet.
	 */
	protected final static String HIDDEN_IN_PROPERTY_SHEET = "hide"; 
	/**