Bug 204090 render a small rptdocument to PDF will be OutofMemory
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/util/TableProcessor.java
public void processNodes( )
		{
			Element ele = element;
			processNodes( ele );
			parent.getChildren( ).add( content );
			content.setParent( parent );
		}
		private void processNodes( Element ele )
		{
			for ( Node node = ele.getFirstChild( ); node != null; node = node
					.getNextSibling( ) )
			{
				assert ( node.getNodeType( ) == Node.ELEMENT_NODE );
				Element element = (Element) node;
				String tagName = element.getTagName( );
				if ( "tr".equals( tagName ) )
				{
					RowState rowState = new RowState( element, cssStyles, content, inlineParent, action );
					rowState.processNodes( );
					columnCount = Math.max( columnCount, rowState
							.getColumnCount( ) );
					++rowCount;
				}
				else if ( "col".equals( tagName ) )
				{
					columnWidth.add( PropertyUtil.getDimensionAttribute( element, "width" ) );
				}
				else if ( "tbody".equals( tagName ) || "thead".equals( tagName )
						|| "tfoot".equals( tagName ) )