jfreechart生成柱状图与饼状图(入门)

jfreechart生成柱状图与饼状图(入门)贴两段代码。

/** * 生成柱状图 */public String genChannelNumBarChart() {try {@SuppressWarnings("unchecked")List<Object[]> lst = channelService.getArticleNumByChannel();int lstSize = lst.size();double[][] data = new double[lstSize][1];String[] rowKeys = new String[lstSize];String[] columnKeys = new String[]{""};int i = 0;for (Object[] obj : lst) {log.debug(obj[0] + "," + obj[1]);data[i] = new double[] { Double.parseDouble(String.valueOf(obj[1])) };rowKeys[i] = String.valueOf(obj[0]);i++;}CategoryDataset dataset = DatasetUtilities.createCategoryDataset(rowKeys, columnKeys, data);JFreeChart chart = ChartFactory.createBarChart3D("栏目文章统计图", "栏目","文章数", dataset, PlotOrientation.VERTICAL, true, false,false);// 通用程序TextTitle textTitle = chart.getTitle();textTitle.setFont(new Font("黑体", Font.BOLD, 15));CategoryPlot plot = chart.getCategoryPlot();CategoryAxis domainAxis = plot.getDomainAxis();domainAxis.setLabelFont(new Font("黑体", Font.BOLD, 15));domainAxis.setTickLabelFont(new Font("黑体", Font.BOLD, 15));ValueAxis valueAxis = plot.getRangeAxis();valueAxis.setLabelFont(new Font("黑体", Font.BOLD, 15));chart.getLegend().setItemFont(new Font("黑体", Font.BOLD, 15));String filename = ServletUtilities.saveChartAsPNG(chart, 600, 400,null, this.getSession());String graphURL = this.getRequest().getContextPath()+ "/DisplayChart?filename=" + filename;log.debug("graphURL:" + graphURL);this.setAttribute("graphURL", graphURL);this.setAttribute("filename", filename);return "channelNumBarChart";} catch (Exception e) {e.printStackTrace();}return "channelNumBarChart";}/** * 生成饼状图 * @return */public String genChannelNumPieChart() {try{@SuppressWarnings("unchecked")List<Object[]> lst = channelService.getArticleNumByChannel();//设置数据集 DefaultPieDataset dataset = new DefaultPieDataset();int i = 0;for (Object[] obj : lst) {log.debug(obj[0] + "," + obj[1]);dataset.setValue(String.valueOf(obj[0]),Double.parseDouble(String.valueOf(obj[1])));i++;}//通过工厂类生成JFreeChart对象 JFreeChart chart = ChartFactory.createPieChart3D("栏目文章发布分布图",dataset, true, false, false);TextTitle textTitle = chart.getTitle();textTitle.setFont(new Font("黑体",Font.BOLD,15));PiePlot pieplot = (PiePlot) chart.getPlot();pieplot.setLabelFont(new Font("宋体", 0, 12));//没有数据的时候显示的内容 pieplot.setNoDataMessage("无数据显示");pieplot.setCircular(false);pieplot.setLabelGap(0.02D);chart.getLegend().setItemFont(new Font("黑体",Font.BOLD,15));//pieplot.getLegendItems().//XYPlot  xyPlot=(XYPlot)chart.getPlot();//xyPlot.getRangeAxis().setLabelFont(new Font("黑体",Font.BOLD,15));String filename = ServletUtilities.saveChartAsPNG(chart, 500, 300,null, this.getSession());String graphURL = this.getRequest().getContextPath()+ "/DisplayChart?filename=" + filename;this.setAttribute("graphURL", graphURL);this.setAttribute("filename", filename);return "channelNumPieChart";}catch(Exception e){e.printStackTrace();}return "channelNumPieChart";}