Bug 213973 [2.2.2]ClassCastException throws out when preview a table share crosstab
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/data/dte/ReportQueryBuilder.java
protected HashMap queryIDs;
	/**
	 * query and result metaData
	 */
	protected HashMap resultMetaData;
	/**
	 * a collection of all the queries
	 */
	protected Collection queries;
	/**
	 * entry point to the report
	 */
	protected Report report;
	/**
	 * the execution context
	 */
	protected ExecutionContext context;
	/**
	 * the max rows per query
	 */
	protected int maxRows = 0;
	protected IQueryContext queryContext;
	protected DataRequestSession dteSession;
	
	/**
	 * used to register the unresolved query reference.
	 */
	protected Map unresolvedQueryReferences = new HashMap( );
	public ReportQueryBuilder( )
	{