Bug 176450 Support link to CSS Feature(Model Part)
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/StructureFactory.java
* @throws IllegalArgumentException
	 *             if the <code>newName</code> is <code>null</code>.
	 */
	public static ComputedColumn newComputedColumn(
			DesignElementHandle element, String newName )
	{
		if ( newName == null )
			throw new IllegalArgumentException(
					"The new column name must not be empty" ); 
		if ( !( element instanceof ReportItemHandle
				|| element instanceof ScalarParameterHandle || element instanceof GroupHandle ) )
			return null;
		String tmpName = BoundDataColumnUtil.makeUniqueName( element, newName,
				null );
		ComputedColumn column = new ComputedColumn( );
		column.setName( tmpName );
		return column;
	}
	/**
	 * Create TOC structure.
	 * 
	 * @return toc object
	 */
	public static TOC createTOC( )
	{
		TOC toc = new TOC( );
		return toc;
	}
	/**
	 * Create TOC structure with expression value.