Bug 202254 Exception is thrown when category values are null and type of X axis is set to DateTime
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/model/data/util/DataSwitch.java
import org.eclipse.birt.chart.model.data.DataPackage;
import org.eclipse.birt.chart.model.data.DataSet;
import org.eclipse.birt.chart.model.data.DateTimeDataElement;
import org.eclipse.birt.chart.model.data.DateTimeDataSet;
import org.eclipse.birt.chart.model.data.NumberDataElement;
import org.eclipse.birt.chart.model.data.NumberDataSet;
import org.eclipse.birt.chart.model.data.OrthogonalSampleData;
import org.eclipse.birt.chart.model.data.Query;
import org.eclipse.birt.chart.model.data.Rule;
import org.eclipse.birt.chart.model.data.SampleData;
import org.eclipse.birt.chart.model.data.SeriesDefinition;
import org.eclipse.birt.chart.model.data.SeriesGrouping;
import org.eclipse.birt.chart.model.data.StockDataSet;
import org.eclipse.birt.chart.model.data.TextDataSet;
import org.eclipse.birt.chart.model.data.Trigger;
import org.eclipse.emf.ecore.EClass;
import org.eclipse.emf.ecore.EObject;
/**
 * <!-- begin-user-doc --> The <b>Switch </b> for the model's inheritance hierarchy. It supports the call
 * {@link #doSwitch(EObject) doSwitch(object)}to invoke the <code>caseXXX</code> method for each class of the model,
 * starting with the actual class of the object and proceeding up the inheritance hierarchy until a non-null result is
 * returned, which is the result of the switch. <!-- end-user-doc -->
 * @see org.eclipse.birt.chart.model.data.DataPackage
 * @generated
 */
public class DataSwitch
{
	/**
	 * The cached model package
	 * <!-- begin-user-doc --> <!-- end-user-doc -->