jfreeChart多元数据之柱形图的生成

程序代码

<%@ page contentType="text/html;charset=GBK"%>
<%@ page import="java.awt.Color,
org.jfree.chart.ChartFactory,
org.jfree.chart.JFreeChart,
org.jfree.chart.plot.PlotOrientation,
org.jfree.chart.servlet.ServletUtilities,
org.jfree.chart.plot.CategoryPlot,
org.jfree.chart.axis.CategoryAxis,
org.jfree.chart.axis.ValueAxis,
org.jfree.data.general.DatasetUtilities,
org.jfree.chart.renderer.category.BarRenderer3D,
org.jfree.chart.labels.StandardCategoryItemLabelGenerator,
org.jfree.chart.axis.AxisLocation"%>
<%
double[][] data = new double[][] {{672, 766, 223, 540, 126},{325, 521, 210, 340, 106},{332, 256, 523, 240, 526}};
String[] rowKeys = {"苹果","梨子","葡萄"};
String[] columnKeys = {"北京","上海","广州","成都","深圳"};
org.jfree.data.category.CategoryDataset dataset = DatasetUtilities.createCategoryDataset(rowKeys, columnKeys, data);

JFreeChart chart = ChartFactory.createBarChart3D("水果销量图统计",
null,
null,
dataset,
PlotOrientation.VERTICAL,
true,false,false);
chart.setBackgroundPaint(Color.WHITE);
CategoryPlot plot = chart.getCategoryPlot();

CategoryAxis domainAxis = plot.getDomainAxis();
plot.setDomainAxis(domainAxis);

ValueAxis rangeAxis = plot.getRangeAxis();
//设置最高的一个 Item 与图片顶端的距离
rangeAxis.setUpperMargin(0.15);
//设置最低的一个 Item 与图片底端的距离
rangeAxis.setLowerMargin(0.15);
plot.setRangeAxis(rangeAxis);
BarRenderer3D renderer = new BarRenderer3D();
renderer.setBaseOutlinePaint(Color.BLACK);
//设置 Wall 的颜色
renderer.setWallPaint(Color.gray);
//设置每种水果代表的柱的颜色
renderer.setSeriesPaint(0, new Color(0, 0, 255));
renderer.setSeriesPaint(1, new Color(0, 100, 255));
renderer.setSeriesPaint(2, Color.GREEN);
//设置每个地区所包含的平行柱的之间距离
renderer.setItemMargin(0.1);
//显示每个柱的数值，并修改该数值的字体属性
renderer.setItemLabelGenerator(new StandardCategoryItemLabelGenerator());
renderer.setItemLabelsVisible(true);
plot.setRenderer(renderer);

//设置柱的透明度
plot.setForegroundAlpha(0.6f);
//设置地区、销量的显示位置
plot.setDomainAxisLocation(AxisLocation.TOP_OR_RIGHT);
plot.setRangeAxisLocation(AxisLocation.BOTTOM_OR_RIGHT);

String filename = ServletUtilities.saveChartAsPNG(chart, 500, 300, null, session);
String graphURL = request.getContextPath() + "/servlet/DisplayChart?filename=" + filename;
%>
<img src="<%= graphURL %>" width=500 height=300 border=0 usemap="#<%= filename %>">

效果: