Bug 212375 [Automation][Regression]Exception occurs when preview a outputParams["xxx"]
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedDataSourceQuery.java
import java.util.Map;
import java.util.logging.Logger;
import org.eclipse.birt.data.engine.api.DataEngineContext;
import org.eclipse.birt.data.engine.api.IBaseDataSetDesign;
import org.eclipse.birt.data.engine.api.IBaseDataSourceDesign;
import org.eclipse.birt.data.engine.api.IBaseQueryDefinition;
import org.eclipse.birt.data.engine.api.IBaseQueryResults;
import org.eclipse.birt.data.engine.api.IPreparedQuery;
import org.eclipse.birt.data.engine.api.IQueryDefinition;
import org.eclipse.birt.data.engine.api.IQueryResults;
import org.eclipse.birt.data.engine.core.DataException;
import org.eclipse.birt.data.engine.executor.DataSetCacheManager;
import org.eclipse.birt.data.engine.odi.IResultIterator;
import org.mozilla.javascript.Scriptable;
/**
 * Base class for a top-level prepared query that has its own data source (either extended data source, or 
 * scripted data source)  
 */
abstract class PreparedDataSourceQuery
		implements
			IPreparedQuery,
			IPreparedQueryService
{
	protected IBaseDataSetDesign dataSetDesign;
	
	protected DataEngineImpl dataEngine;
	protected IQueryDefinition queryDefn;
	protected PreparedQuery preparedQuery;
	protected Map appContext;