Bug 204229 [Automation][Regression]Exception is thrown when preview reportdesign in webviewer
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/document/util/ExprDataReader1.java
rowExprsRAIs.seek( rowOffsetAbsolute + this.metaOffset ); 
			rowExprsDis = new DataInputStream( rowExprsRAIs );
		}
		else 
		{
			rowLenRAIs.seek( absoluteRowIndex * 8  );
			long rowOffsetAbsolute = IOUtil.readLong( this.rowLenDis );
			
			rowExprsRAIs.seek( rowOffsetAbsolute + this.metaOffset ); 
			rowExprsDis = new DataInputStream( rowExprsRAIs );
		}
	}
	
	/**
	 * @throws IOException
	 * @throws DataException 
	 */
	private Map getValueMap( ) throws IOException, DataException
	{
		Map valueMap = new HashMap( );
		int exprCount = IOUtil.readInt( rowExprsDis );
		for ( int i = 0; i < exprCount; i++ )
		{
			String exprID = this.exprKeys.get( i ).toString( );
			Object exprValue = IOUtil.readObject( rowExprsDis );
			if ( RowSaveUtil.EXCEPTION_INDICATOR.equals( exprValue ) )
				continue;
			valueMap.put( exprID, exprValue );
		}