Gráfico jsp com Cewolf

public class CertificacaoEstadoDataSet implements DatasetProducer {
			 
			
			public Object produceDataset(Map arg0) throws DatasetProduceException {
				
				// Criando um Dataset para o gráfico
				DefaultPieDataset ds = new DefaultPieDataset();
				
				
								
						// Inserindo no DataSet ds.setValue("TOTAL",
						// new Double(100));
						ds.setValue("A", new Double(32));
						ds.setValue("B", new Double(33));
						
				return ds;
			}
		public boolean hasExpired(Map arg0, Date arg1) {
				return true;
				// Se quisessemos que os dataset expirasse em 5 segundos
				// colocariamos
				// return (System.currentTimeMillis() - since.getTime()) >
				// 5000;
			}
		}

//na jsp
<jsp:useBean
			id="graficoDS" class="classeDataSet()" /> <cewolf:chart
			id="grafico"  type="pie">
			<cewolf:gradientpaint>
				<cewolf:point x="0" y="0" color="#FBFBFB" />
				<cewolf:point x="400" y="0" color="#F3F3F3" />
			</cewolf:gradientpaint>
			<cewolf:data>
				<cewolf:producer id="graficoDS" />
			</cewolf:data>
		</cewolf:chart> <cewolf:img chartid="grafico" renderer="/cewolf" width="400"
			height="200" />