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/extension/IReportItemPresentation.java
* This function is needed because the actual size may not be the same as
	 * the design-time size.
	 * 
	 * @return the size of the extended item. Return null if the size does not
	 *         matter or can not be determined.
	 */
	public Size getSize( );
	/**
	 * Performs clean up work
	 */
	public void finish( );
	/**
	 * @deprecated implement #init(IReportItemPresentationInfo) instead.
	 * Set dynamic style.
	 */
	public void setDynamicStyle( IStyle style );
	
	/**
	 * Set the content which is transformed from extended item. Extended item
	 * can process some properties itself, such as bookmark, style etc.
	 * 
	 * @deprecated implement #init(IReportItemPresentationInfo) instead.
	 * @param content
	 *            content which is transformed from extended item.
	 */
	public void setExtendedItemContent( IContent content );
	
	public IReportItemPresentationInfo getPresentationConfig( );
}