Bug 211175 ClassCastException thrown when implementing IReportItemQuery
When implementing IReportItemQuery's method, public IDataQueryDefinition[] createReportQueries(IDataQueryDefinition parent) throws BirtException, even if the impl method returns IDataQueryDefinition[], ClassCastException will be thrown during preview, the error log is as follows: java.lang.ClassCastException: [Lorg.eclipse.birt.data.engine.api.IDataQueryDefinition; at org.eclipse.birt.report.engine.executor.ExtendedGenerateExecutor.generateContent(ExtendedGenerateExecutor.java:91) at org.eclipse.birt.report.engine.executor.ExtendedGenerateExecutor.execute(ExtendedGenerateExecutor.java:72) at org.eclipse.birt.report.engine.executor.ExtendedItemExecutor.execute(ExtendedItemExecutor.java:60) at org.eclipse.birt.report.engine.internal.executor.dup.SuppressDuplicateItemExecutor.execute(SuppressDuplicateItemExecutor.java:42) If the method returns IBaseQueryDefinition[], it's ok. Look at the engine code, there's something wrong of class casting when generating content.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/ExtendedGenerateExecutor.java
import org.eclipse.birt.data.engine.api.IDataQueryDefinition;
import org.eclipse.birt.report.engine.api.EngineException;
import org.eclipse.birt.report.engine.content.IContent;
import org.eclipse.birt.report.engine.content.IForeignContent;
import org.eclipse.birt.report.engine.data.IDataEngine;
import org.eclipse.birt.report.engine.data.dte.SingleCubeResultSet;
import org.eclipse.birt.report.engine.data.dte.SingleQueryResultSet;
import org.eclipse.birt.report.engine.extension.IBaseResultSet;
import org.eclipse.birt.report.engine.extension.ICubeResultSet;
import org.eclipse.birt.report.engine.extension.IQueryResultSet;
import org.eclipse.birt.report.engine.extension.IReportItemGeneration;
import org.eclipse.birt.report.engine.extension.IReportItemGenerationInfo;
import org.eclipse.birt.report.engine.extension.internal.ReportItemGenerationInfo;
import org.eclipse.birt.report.engine.i18n.MessageConstants;
import org.eclipse.birt.report.engine.ir.ExtendedItemDesign;
import org.eclipse.birt.report.model.api.ExtendedItemHandle;
public class ExtendedGenerateExecutor extends QueryItemExecutor
{
	IReportItemGeneration itemGeneration;
	IBaseResultSet[] rsets;
	public ExtendedGenerateExecutor( ExecutorManager manager,
			IReportItemGeneration itemGeneration )
	{
		super( manager, -1 );
		this.itemGeneration = itemGeneration;
	}
	
	public void close( )
	{
		closeQueries( );