


JFreeChart chart generation examples (pie charts, bar charts, line charts, time series charts)
import java.awt.BasicStroke; import java.awt.Color; import java.io.FileOutputStream; import java.io.IOException; import java.text.DateFormat; import java.text.SimpleDateFormat; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServlet; import org.jfree.data.category.CategoryDataset; import org.jfree.data.category.DefaultCategoryDataset; import org.jfree.data.general.DefaultPieDataset; import org.jfree.data.time.Day; import org.jfree.data.time.TimeSeries; import org.jfree.data.time.TimeSeriesCollection; import org.jfree.data.xy.XYDataset; import org.jfree.chart.*; import org.jfree.chart.axis.CategoryAxis; import org.jfree.chart.axis.DateAxis; import org.jfree.chart.axis.DateTickUnit; import org.jfree.chart.axis.DateTickUnitType; import org.jfree.chart.axis.ValueAxis; import org.jfree.chart.plot.CategoryPlot; import org.jfree.chart.plot.PiePlot; import org.jfree.chart.plot.PlotOrientation; import org.jfree.chart.plot.XYPlot; import org.jfree.chart.renderer.category.LineAndShapeRenderer; import org.jfree.chart.servlet.ServletUtilities; import org.jfree.chart.title.TextTitle; import com.lowagie.text.Font; import demo.BarChart3DDemo1; /** * Servlet implementation class ChartDemoServlet */ public class ChartDemoServlet extends HttpServlet { private static final long serialVersionUID = 1L; public ChartDemoServlet() { super(); // TODO Auto-generated constructor stub } public void service(ServletRequest request, ServletResponse response) throws ServletException, IOException{ response.setContentType("image/jpeg"); DefaultPieDataset data = getDataSet(); CategoryDataset dataset = getDataSet2(); DefaultCategoryDataset linedataset = createDataset(); //JFreeChart chart = ChartFactory.createPieChart3D("水果产量图", data, true, false, false); /** JFreeChart chart = ChartFactory.createBarChart3D( "水果产量图", // 图表标题 "水果", // 目录轴的显示标签 "产量", // 数值轴的显示标签 dataset, // 数据集 PlotOrientation.VERTICAL, // 图表方向:水平、垂直 true, // 是否显示图例(对于简单的柱状图必须是 false) false, // 是否生成工具 false // 是否生成 URL 链接 ); **/ JFreeChart chart = ChartFactory.createLineChart( "折线图", // 图表标题 "时间", // 横轴显示标签 "销售额(百万)", // 纵轴显示标签 linedataset, // 数据集 PlotOrientation.VERTICAL, // 图表方向:水平、垂直 true, // 是否显示图例标识(对于简单的柱状图必须是 false) true, // 是否生成工具 false // 是否生成 URL 链接 ); /* JFreeChart chart=ChartFactory.createTimeSeriesChart( "编程词典全国销量统计" , "销售月份" , "销量(份)" , createtimedata() , false , false , false ); */ /* * jfreechart1.0.13生成的图片中,中文都以方框形式显示,中文乱码解决如下(包括:饼图、柱状图、时序图、折线图)。 */ /***设置饼图相关属性***/ /* PiePlot pieplot = (PiePlot) chart.getPlot();//获取饼图区域对象。 pieplot.setLabelFont(new java.awt.Font("宋体",0,12)); pieplot.setNoDataMessage("无数据显示"); //没有数据的时候显示的内容 pieplot.setCircular(false); pieplot.setLabelGap(0.02D); TextTitle txtTitle = null; txtTitle = chart.getTitle(); java.awt.Font font = new java.awt.Font("宋体", Font.BOLD, 16); txtTitle.setFont(font);//解决标题中文乱码 chart.getLegend().setItemFont(font); chart.setBackgroundPaint(new Color(232,232,232));//设定背景 pieplot.setBackgroundPaint(Color.white); //设定图表数据显示部分背景色 */ /***设置柱状图、折线图相关属性***/ CategoryPlot catplot=chart.getCategoryPlot(); //获取柱状图、折线图区域对象。 CategoryAxis domainAxis=catplot.getDomainAxis(); catplot.setNoDataMessage("无数据显示");//没有数据的时候显示的内容 //列表标题 TextTitle txtTitle = null; txtTitle = chart.getTitle(); txtTitle.setFont(new java.awt.Font("黑体",Font.BOLD,14)); //水平底部列表 domainAxis.setLabelFont(new java.awt.Font("黑体",Font.BOLD,14)); //水平底部标题 domainAxis.setTickLabelFont(new java.awt.Font("宋体",Font.BOLD,12)); //垂直标题 ValueAxis rangeAxis=catplot.getRangeAxis();//获取柱状 rangeAxis.setLabelFont(new java.awt.Font("黑体",Font.BOLD,15)); chart.getLegend().setItemFont(new java.awt.Font("黑体", Font.BOLD, 15)); //获得renderer LineAndShapeRenderer lineAndShapeRenderer =(LineAndShapeRenderer)catplot.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)); //这里是虚线,默认是直线 */ /***设置时序图相关属性***/ /** XYPlot xyplot = (XYPlot) chart.getPlot();//获取时序图区域对象。 //列表标题 TextTitle txtTitle = null; txtTitle = chart.getTitle(); txtTitle.setFont(new java.awt.Font("黑体",Font.BOLD,15)); //纵轴字体 xyplot.getRangeAxis().setLabelFont(new java.awt.Font("宋体", Font.BOLD, 12)); //横轴框里的标题字体:显示图例 //chart.getLegend().setItemFont(new java.awt.Font("宋体", Font.ITALIC, 12)); //横轴列表字体 xyplot.getDomainAxis().setTickLabelFont(new java.awt.Font("新宋体", 1, 12)); //横轴小标题字体 xyplot.getDomainAxis().setLabelFont(new java.awt.Font("新宋体", 1, 12)); chart.setBackgroundPaint(new Color(252,175,134)); //设置背景色 xyplot.setDomainGridlinesVisible(false); //设置网格不显示 //获取时间轴对象 DateAxis dateAxis = (DateAxis) xyplot.getDomainAxis(); //dateAxis.setLabelFont(new java.awt.Font("黑体", Font.ITALIC , 18)); //设置时间轴字体 dateAxis.setLowerMargin(0.0);//设置时间轴上显示的最小值 DateFormat format = new SimpleDateFormat("MM月份"); //创建日期格式对象 //创建DateTickUnit对象 DateTickUnit dtu = new DateTickUnit(DateTickUnitType.DAY,29,format); dateAxis.setTickUnit(dtu);//设置日期轴的日期标签 **/ //chart.getTitle().setFont(new java.awt.Font("宋体", Font.BOLD, 15)); //chart.getLegend().setItemFont(new java.awt.Font("黑体", Font.BOLD, 15)); //CategoryAxis domainAxis = plot.getDomainAxis(); /*------设置X轴坐标上的文字-----------*/ //domainAxis.setTickLabelFont(new java.awt.Font("黑体", Font.PLAIN, 11)); /*------设置X轴的标题文字------------*/ //domainAxis.setLabelFont(new java.awt.Font("宋体", Font.PLAIN, 12)); //NumberAxis numberaxis = (NumberAxis) plot.getRangeAxis(); /*------设置Y轴坐标上的文字-----------*/ //numberaxis.setTickLabelFont(new java.awt.Font("黑体", Font.PLAIN, 12)); /*------设置Y轴的标题文字------------*/ //numberaxis.setLabelFont(new java.awt.Font("黑体", Font.PLAIN, 12)); FileOutputStream fos_jpg=null; try{ fos_jpg=new FileOutputStream("D:\\ok_bing.jpg"); /* * 第二个参数如果为100,会报异常: * java.lang.IllegalArgumentException: The 'quality' must be in the range 0.0f to 1.0f * 限制quality必须小于等于1,把100改成 0.1f。 */ ChartUtilities.writeChartAsJPEG(fos_jpg, 0.99f, chart, 600, 300, null); }catch(Exception e){ System.out.println("[e]"+e); }finally{ try{ fos_jpg.close(); }catch(Exception e){ } } } /** * 获取一个演示用的简单数据集对象 * @return */ //生成饼图数据 private static DefaultPieDataset getDataSet() { DefaultPieDataset dataset = new DefaultPieDataset(); dataset.setValue("苹果",100); dataset.setValue("梨子",200); dataset.setValue("葡萄",300); dataset.setValue("香蕉",400); dataset.setValue("荔枝",500); return dataset; } //生成柱状图数据 private static CategoryDataset getDataSet2() { DefaultCategoryDataset dataset = new DefaultCategoryDataset(); dataset.addValue(100, "北京", "苹果"); dataset.addValue(100, "上海", "苹果"); dataset.addValue(100, "广州", "苹果"); dataset.addValue(200, "北京", "梨子"); dataset.addValue(200, "上海", "梨子"); dataset.addValue(200, "广州", "梨子"); dataset.addValue(300, "北京", "葡萄"); dataset.addValue(300, "上海", "葡萄"); dataset.addValue(300, "广州", "葡萄"); dataset.addValue(400, "北京", "香蕉"); dataset.addValue(400, "上海", "香蕉"); dataset.addValue(400, "广州", "香蕉"); dataset.addValue(500, "北京", "荔枝"); dataset.addValue(500, "上海", "荔枝"); dataset.addValue(500, "广州", "荔枝"); return dataset; } //生成折线图数据 public static DefaultCategoryDataset createDataset() { DefaultCategoryDataset linedataset = new DefaultCategoryDataset(); // 各曲线名称 String series1 = "冰箱"; String series2 = "彩电"; String series3 = "洗衣机"; //横轴名称(列名称) String type1 = "1月"; String type2 = "2月"; String type3 = "3月"; String type4 = "4月"; String type5 = "5月"; linedataset.addValue(0.0, series1, type1); linedataset.addValue(4.2, series1, type2); linedataset.addValue(3.9, series1, type3); linedataset.addValue(3.2, series1, type4); linedataset.addValue(3.0, series1, type5); linedataset.addValue(1.0, series2, type1); linedataset.addValue(5.2, series2, type2); linedataset.addValue(7.9, series2, type3); linedataset.addValue(8.9, series2, type4); linedataset.addValue(9.2, series2, type5); linedataset.addValue(2.0, series3, type1); linedataset.addValue(9.2, series3, type2); linedataset.addValue(8.9, series3, type3); linedataset.addValue(9.9, series3, type4); linedataset.addValue(10.9, series3, type5); return linedataset; } //生成时序图数据 public static XYDataset createtimedata() { //实例化TimeSeries对象 TimeSeries timeseries = new TimeSeries("Data"); Day day = new Day(1, 1, 2008); //实例化Day double d = 3000D;//添加一年365天的数据 for (int i = 0; i < 365; i++) { d = d + (Math.random() - 0.5) * 10; //创建随机数据 timeseries.add(day, d); //向数据集合中添加数据 day = (Day) day.next(); } //创建TimeSeriesCollection集合对象 TimeSeriesCollection timeSeriesCollection =new TimeSeriesCollection(timeseries); //返回数据集合对象 return timeSeriesCollection; } }

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