用JfreeChart画散点图，查看JfreeChart的Demo，写的都挺复杂的，关键是Demo中把简单的事情复杂化了，比如展示的例子是一个正弦曲线什么的，让初次画散点图的我们摸不着头脑。关键是他们得到数据集搞得太过复杂，后来想明白了，不就是二维数组嘛。想通了这一点，一切问题都解决了，不过，对于我们项目的特殊要求，并不是只画几个点那么简单，还要加上区域范围与文字说明，在查看文档及自己摸索下，2天时间，终于搞定。下面分享一下成果，呵，还是有点成就感的。
首先，看画图的API，参数有：
ChartFactory.createScatterPlot（），其中，有一个xydataset，那么，我们先要知道这个xydataset是什么结构的，再看所需xydataset，散点图，也就是单独画出点，也就是一个二维数据了，x ，y坐标嘛！
那么，先做好准备工作，***步，拿数据，这就不用啰嗦了，就是得到一个List也好，Set也行。
第二步，加载到数据集：
- /**
- *
- * @param xydatalist
- * @param bloods
- * @return
- */
- public static XYDataset createxydataset(List<PressureBean> xydatalist,
- String bloods) {
- DefaultXYDataset xydataset = new DefaultXYDataset();
- int size = xydatalist.size();
- double[][] datas = new double[2][size];
- for (int i = 0; i < size; i++) {
- PressureBean pres = xydatalist.get(i);
- int sys = pres.getSyspress();//收缩压
- int dia = pres.getDiapress();//舒张压
- datas[0][i] = sys;
- datas[1][i] = dia;
- }
- xydataset.addSeries(bloods, datas);
- return xydataset;
- }
下一步，另外一个准备工作，画图方法：
- public static JFreeChart createChart(XYDataset xydataset,
- String bloodcattile, String shou, String shu, String nobloodData,
- String bloods, String nomal, String fore, String one, String two,
- List<PressureBean> list, Log log) {
- // 有可能用户在后面的版本中故意输入不正常数值，但是为了保证图片画图的完整，这里先计算
- // 用户血压值的***值。
- int maxpress = 160;
- int addmax = 20;
- if (list != null && list.size() > 0) {
- Iterator<PressureBean> it = list.iterator();
- while (it.hasNext()) {
- PressureBean pres = it.next();
- if (maxpress < pres.getDiapress()) {
- maxpress = pres.getDiapress();
- }
- if (maxpress < pres.getSyspress()) {
- maxpress = pres.getSyspress();
- }
- }
- maxpress += addmax;
- log.info("high press value is =" + maxpress);
- }
- JFreeChart jfreechart = ChartFactory.createScatterPlot(bloodcattile,
- shou, shu, xydataset, PlotOrientation.VERTICAL, true, false,
- false);
- jfreechart.setBackgroundPaint(Color.white);
- jfreechart.setBorderPaint(Color.GREEN);
- jfreechart.setBorderStroke(new BasicStroke(1.5f));
- XYPlot xyplot = (XYPlot) jfreechart.getPlot();
- xyplot.setNoDataMessage(nobloodData);
- xyplot.setNoDataMessageFont(new Font("", Font.BOLD, 14));
- xyplot.setNoDataMessagePaint(new Color(87, 149, 117));
- xyplot.setBackgroundPaint(new Color(255, 253, 246));
- ValueAxis vaaxis = xyplot.getDomainAxis();
- vaaxis.setAxisLineStroke(new BasicStroke(1.5f));
- ValueAxis va = xyplot.getDomainAxis(0);
- va.setAxisLineStroke(new BasicStroke(1.5f));
- va.setAxisLineStroke(new BasicStroke(1.5f)); // 坐标轴粗细
- va.setAxisLinePaint(new Color(215, 215, 215)); // 坐标轴颜色
- xyplot.setOutlineStroke(new BasicStroke(1.5f)); // 边框粗细
- va.setLabelPaint(new Color(10, 10, 10)); // 坐标轴标题颜色
- va.setTickLabelPaint(new Color(102, 102, 102)); // 坐标轴标尺值颜色
- ValueAxis axis = xyplot.getRangeAxis();
- axis.setAxisLineStroke(new BasicStroke(1.5f));
- XYLineAndShapeRenderer xylineandshaperenderer = (XYLineAndShapeRenderer) xyplot
- .getRenderer();
- xylineandshaperenderer.setSeriesOutlinePaint(0, Color.WHITE);
- xylineandshaperenderer.setUseOutlinePaint(true);
- NumberAxis numberaxis = (NumberAxis) xyplot.getDomainAxis();
- numberaxis.setAutoRangeIncludesZero(false);
- numberaxis.setTickMarkInsideLength(2.0F);
- numberaxis.setTickMarkOutsideLength(0.0F);
- numberaxis.setAxisLineStroke(new BasicStroke(1.5f));
- numberaxis.setUpperBound(maxpress);
- numberaxis.setLowerBound(60);//最小值设置为60
- NumberAxis numberaxis1 = (NumberAxis) xyplot.getRangeAxis();
- numberaxis1.setTickMarkInsideLength(2.0F);
- numberaxis1.setTickMarkOutsideLength(0.0F);
- numberaxis1.setUpperBound(105d);
- numberaxis1.setLowerBound(35);
- numberaxis1.setAxisLineStroke(new BasicStroke(1.5f));
- // if (xydataset != null) {
- XYBoxAnnotation box = new XYBoxAnnotation(0, 0, 89, 59); //正常血压所在区域内边界
- XYBoxAnnotation box1 = new XYBoxAnnotation(0, 0, 119, 79);//高血压前期所在区域内边界
- XYBoxAnnotation box2 = new XYBoxAnnotation(0, 0, 139, 89);//高血压一期所在区域内边界
- XYBoxAnnotation box3 = new XYBoxAnnotation(0, 0, 159, 99);//高血压二期所在区域内边界
- XYTextAnnotation text1 = new XYTextAnnotation(nomal, 70, 62.5);//标识“正常”
- XYTextAnnotation text = new XYTextAnnotation(fore, 70, 82.5);//“高血压前期”
- XYTextAnnotation text2 = new XYTextAnnotation(one, 70, 91.5);//“高血压一期”
- XYTextAnnotation text3 = new XYTextAnnotation(two, 70, 101.5);//“高血压二期”
- //将上面的边界线条，说明文字加入到xyplot中。
- xyplot.addAnnotation(box);
- xyplot.addAnnotation(box1);
- xyplot.addAnnotation(box2);
- xyplot.addAnnotation(box3);
- xyplot.addAnnotation(text);
- xyplot.addAnnotation(text1);
- xyplot.addAnnotation(text2);
- xyplot.addAnnotation(text3);
- // }
- return jfreechart;
- }
***一步，返回图片URL
- public static void drawScatterChart(IrisIoInterface io, Log log,
- XYDataset xydataSet, String title, String shou, String shu,
- String nodata, String boolds, String nomal, String fore,
- String one, String two, List<PressureBean> list) {
- JFreeChart chart = createChart(xydataSet, title, shou, shu, nodata,
- boolds, nomal, fore, one, two, list, log);
- HttpServletRequest request = io.getRequest();
- String filename = "";
- String graphURL = "";
- try {
- filename = ServletUtilities.saveChartAsPNG(chart, 400, 300, null,
- io.getSession());
- graphURL = request.getContextPath() + "/displayChart?filename="
- + filename;
- } catch (IOException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- log.error(e);
- }
- io.setData("filename", filename, BeanShare.BEAN_SHARE_REQUEST);
- io.setData("scatterurl", graphURL, BeanShare.BEAN_SHARE_REQUEST);
- }
效果图：
原文链接：http://juliana-only.iteye.com/blog/544104
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