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JFreeChart核心类库介绍:
研究jfreechart源码发现源码的主要由两个大的包组成:org.jfree.chart,org.jfree.data。其中前者主要与图形 本身有关,后者与图形显示的数据有关。具体研究如果大家有兴趣的话可以自己研究,以后有时间我会告诉大家怎么去 研究源码。 核心类主要有: org.jfree.chart.JFreeChart:图表对象,任何类型的图表的最终表现形式都是在该对象进行一些属性的定制。JFreeChart引擎本身提供了一个工厂类用于创建不同类型的图表对象 org.jfree.data.category.XXXDataSet:数据集对象,用于提供显示图表所用的数据。根据不同类型的图表对应着很多类型的数据集对象类 org.jfree.chart.plot.XXXPlot:图表区域对象,基本上这个对象决定着什么样式的图表,创建该对象的时候需要Axis、Renderer以及数据集对象的支持 org.jfree.chart.axis.XXXAxis:用于处理图表的两个轴:纵轴和横轴 org.jfree.chart.render.XXXRender:负责如何显示一个图表对象 org.jfree.chart.urls.XXXURLGenerator:用于生成Web图表中每个项目的鼠标点击链接 XXXXXToolTipGenerator:用于生成图象的帮助提示,不同类型图表对应不同类型的工具提示类.
折线图
折线图的dataset 两种CatagoryDataset接口(具体实现类是DefaultCategoryDataset),XYDataset 接口 1、CatagoryDataset接口: A、创建一个数据源(dataset): private static CategoryDataset createDataset() { String series1 = “First”; String series2 = “Second”; String series3 = “Third”; String type1 = “Type 1″; String type2 = “Type 2″; String type3 = “Type 3″; String type4 = “Type 4″; String type5 = “Type 5″; String type6 = “Type 6″; String type7 = “Type 7″; String type8 = “Type 8″; DefaultCategoryDataset defaultcategorydataset = new DefaultCategoryDataset(); defaultcategorydataset.addValue(1.0D, series1, type1); defaultcategorydataset.addValue(4D, series1, type2); defaultcategorydataset.addValue(3D, series1, type3); defaultcategorydataset.addValue(5D, series1, type4); defaultcategorydataset.addValue(5D, series1, type5); defaultcategorydataset.addValue(7D, series1, type6); defaultcategorydataset.addValue(7D, series1, type7); defaultcategorydataset.addValue(8D, series1, type8); defaultcategorydataset.addValue(5D, series2, type1); defaultcategorydataset.addValue(7D, series2, type2); defaultcategorydataset.addValue(6D, series2, type3); defaultcategorydataset.addValue(8D, series2, type4); defaultcategorydataset.addValue(4D, series2, type5); defaultcategorydataset.addValue(4D, series2, type6); defaultcategorydataset.addValue(2D, series2, type7); defaultcategorydataset.addValue(1.0D, series2, type8); defaultcategorydataset.addValue(4D, series3, type1); defaultcategorydataset.addValue(3D, series3, type2); defaultcategorydataset.addValue(2D, series3, type3); defaultcategorydataset.addValue(3D, series3, type4); defaultcategorydataset.addValue(6D, series3, type5); defaultcategorydataset.addValue(3D, series3, type6); defaultcategorydataset.addValue(4D, series3, type7); defaultcategorydataset.addValue(3D, series3, type8); return defaultcategorydataset; } B、由ChartFactory 产生 JFreeChart 对象 (与上面重复的部分就不再注释) private static JFreeChart createChart(CategoryDataset categorydataset) { JFreeChart jfreechart = ChartFactory.createLineChart(”Line Chart Demo 1″, “Type”, “Value”, categorydataset, PlotOrientation.VERTICAL, true, true, false); jfreechart.setBackgroundPaint(Color.white); CategoryPlot categoryplot = (CategoryPlot)jfreechart.getPlot(); categoryplot.setBackgroundPaint(Color.lightGray); categoryplot.setRangeGridlinePaint(Color.white); NumberAxis numberaxis = (NumberAxis)categoryplot.getRangeAxis(); numberaxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits()); numberaxis.setAutoRangeIncludesZero(true); //获得renderer 注意这里是下嗍造型到lineandshaperenderer!! LineAndShapeRenderer lineandshaperenderer = (LineAndShapeRenderer)categoryplot.getRenderer(); lineandshaperenderer.setShapesVisible(true); //series 点(即数据点)可见 lineandshaperenderer.setSeriesStroke(0, new BasicStroke(2.0F, 1, 1, 1.0F, new float[] { 10F, 6F }, 0.0F)); //定义series为”First”的(即series1)点之间的连线 ,这里是虚线,默认是直线 lineandshaperenderer.setSeriesStroke(1, new BasicStroke(2.0F, 1, 1, 1.0F, new float[] { 6F, 6F }, 0.0F)); //定义series为”Second”的(即series2)点之间的连线 lineandshaperenderer.setSeriesStroke(2, new BasicStroke(2.0F, 1, 1, 1.0F, new float[] { 2.0F, 6F }, 0.0F)); //定义series为”Third”的(即series3)点之间的连线 return jfreechart; } 一些重要的方法: lineandshaperenderer.setLineVisible(true) //series 点(即数据点)间有连线可见 2、XYDataset 接口: A、创建一个数据源(dataset): private static XYDataset createDataset() { XYSeries xyseries = new XYSeries(”First”); //先产生XYSeries 对象 xyseries.add(1.0D, 1.0D); xyseries.add(2D, 4D); xyseries.add(3D, 3D); xyseries.add(4D, 5D); xyseries.add(5D, 5D); xyseries.add(6D, 7D); xyseries.add(7D, 7D); xyseries.add(8D, 8D); XYSeries xyseries1 = new XYSeries(”Second”); xyseries1.add(1.0D, 5D); xyseries1.add(2D, 7D); xyseries1.add(3D, 6D); xyseries1.add(4D, 8D); xyseries1.add(5D, 4D); xyseries1.add(6D, 4D); xyseries1.add(7D, 2D); xyseries1.add(8D, 1.0D); XYSeries xyseries2 = new XYSeries(”Third”); xyseries2.add(3D, 4D); xyseries2.add(4D, 3D); xyseries2.add(5D, 2D); xyseries2.add(6D, 3D); xyseries2.add(7D, 6D); xyseries2.add(8D, 3D); xyseries2.add(9D, 4D); xyseries2.add(10D, 3D); XYSeriesCollection xyseriescollection = new XYSeriesCollection(); //再用XYSeriesCollection添加入XYSeries 对象 xyseriescollection.addSeries(xyseries); xyseriescollection.addSeries(xyseries1); xyseriescollection.addSeries(xyseries2); return xyseriescollection; } B、由ChartFactory 产生 JFreeChart 对象 private static JFreeChart createChart(XYDataset xydataset) { JFreeChart jfreechart = ChartFactory.createXYLineChart(”Line Chart Demo 2″, “X”, “Y”, xydataset, PlotOrientation.VERTICAL, true, true, false); jfreechart.setBackgroundPaint(Color.white); XYPlot xyplot = (XYPlot)jfreechart.getPlot(); //获得 plot:XYPlot!! xyplot.setBackgroundPaint(Color.lightGray); //设定图表数据显示部分背景色 xyplot.setAxisOffset(new RectangleInsets(5D, 5D, 5D, 5D)); //设定坐标轴与图表数据显示部分距离 xyplot.setDomainGridlinePaint(Color.white); //网格线颜色 xyplot.setRangeGridlinePaint(Color.white); //获得 renderer 注意这里是XYLineAndShapeRenderer !! XYLineAndShapeRenderer xylineandshaperenderer = (XYLineAndShapeRenderer)xyplot.getRenderer(); xylineandshaperenderer.setShapesVisible(true); //数据点可见 xylineandshaperenderer.setShapesFilled(true); //数据点被填充即不是空心点 NumberAxis numberaxis = (NumberAxis)xyplot.getRangeAxis(); numberaxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits()); return jfreechart; } 一些重要的方法: XYLineAndShapeRenderer xylineandshaperenderer = new XYLineAndShapeRenderer(); xylineandshaperenderer.setSeriesLinesVisible(0, false); //第一个XYSeries数据点间连线不可见 xylineandshaperenderer.setSeriesShapesVisible(1, false); //第二个XYSeries数据点不可见 xyplot.setRenderer(xylineandshaperenderer);转载地址:http://wyrvi.baihongyu.com/