Bug 181121 Model should provide utility method for cube to get correspond dimension key.
In model cube handle, the relation of cube data set and dimension data sets are managed by a series of dimension condition handles.We need model to add utility method so that we can easily get corresponding dimension data set column names according to given cube dimension keys.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/DimensionConditionHandle.java
import org.eclipse.birt.report.model.api.elements.structures.DimensionCondition;
import org.eclipse.birt.report.model.api.olap.HierarchyHandle;
import org.eclipse.birt.report.model.core.DesignElement;
import org.eclipse.birt.report.model.core.Structure;
import org.eclipse.birt.report.model.metadata.ElementRefValue;
/**
 * Represents the handle of the cube-dimension/hierarchy join condition.
 * 
 * <p>
 * <dl>
 * <dt><strong>Primary Keys </strong></dt>
 * <dd>Primary keys define a list of primary key to do the join actions between
 * cube and hierarchy in dimension. Each one in the list must be one of the data
 * set column in data set defined in cube.</dd>
 * <dt><strong>Hierarchy</strong></dt>
 * <dd>Hierarchy refers a hierarchy element in one of the dimension in the
 * cube.</dd>
 * </dl>
 * 
 */
public class DimensionConditionHandle extends StructureHandle
{
	/**
	 * Constructs the handle of the cube join condition.
	 * 
	 * @param valueHandle
	 *            the value handle for the cube join condition list of one
	 *            property
	 * @param index
	 *            the position of this join condition in the list