关于POJO中setter的一个小疑问

				chart = new ChartBO().setSeries(series.toArray(new Serie[] {}))

						.setBackgroundColor(chartConfig.getBackgroundColor())

						.setColor(chartConfig.getColor())

						.setCalculable(chartConfig.isCalculable())

						.setAnimation(chartConfig.isAnimation())

						.setTitle(chartConfig.getTitle())

						.setToolbox(chartConfig.getToolbox())

						.setTooltip(chartConfig.getTooltip())

						.setLegend(chartConfig.getLegend())

						.setDataZoom(chartConfig.getDataZoom())

						.setGrid(chartConfig.getGrid())

						.setNoDataText(chartConfig.getNoDataText())

						.setOthers(chartConfig.getProperties());