步骤1,下载jfreechart的jar,及相关jar包
步骤2,
<%@ page contentType="text/html;charset=UTF-8"%>
<%@ page
import="org.jfree.chart.ChartFactory,org.jfree.chart.JFreeChart,org.jfree.chart.plot.PlotOrientation,org.jfree.chart.servlet.ServletUtilities,org.jfree.data.category.CategoryDataset,org.jfree.data.general.DatasetUtilities,org.jfree.chart.plot.*,org.jfree.chart.labels.*,org.jfree.chart.renderer.category.BarRenderer3D,java.awt.*,org.jfree.ui.*,org.jfree.chart.axis.AxisLocation,org.jfree.chart.title.TextTitle,org.jfree.chart.axis.CategoryAxis,org.jfree.chart.axis.NumberAxis"%>
<%
double[][] data = new double[][] { { 1310, 1220, 1110, 1000 },
{ 720, 700, 680, 640 }, { 1130, 1020, 980, 800 },
{ 440, 400, 360, 300 } };
String[] rowKeys = { "猪肉", "牛肉", "鸡肉", "鱼肉" };
String[] columnKeys = { "广州", "深圳", "东莞", "佛山" };
CategoryDataset dataset = DatasetUtilities.createCategoryDataset(
rowKeys, columnKeys, data);
JFreeChart chart = ChartFactory.createBarChart3D("", "肉类", "销量",
dataset, PlotOrientation.VERTICAL, true, true, false);
CategoryPlot plot = chart.getCategoryPlot();
//设置字体,不然会中文乱码的
Font font = new Font("宋体", Font.BOLD, 16);
TextTitle title = new TextTitle("肉类销量统计图", font);
//副标题
TextTitle subtitle = new TextTitle("副标题", new Font("黑体", Font.BOLD,
12));
chart.addSubtitle(subtitle);
chart.setTitle(title); //标题
NumberAxis numberaxis = (NumberAxis) plot.getRangeAxis();
CategoryAxis domainAxis = plot.getDomainAxis();
/*------设置X轴坐标上的文字-----------*/
domainAxis.setTickLabelFont(new Font("sans-serif", Font.PLAIN, 11));
/*------设置X轴的标题文字------------*/
domainAxis.setLabelFont(new Font("宋体", Font.PLAIN, 12));
/*------设置Y轴坐标上的文字-----------*/
numberaxis.setTickLabelFont(new Font("sans-serif", Font.PLAIN, 12));
/*------设置Y轴的标题文字------------*/
numberaxis.setLabelFont(new Font("黑体", Font.PLAIN, 12));
/*------这句代码解决了底部汉字乱码的问题-----------*/
chart.getLegend().setItemFont(new Font("宋体", Font.PLAIN, 12));
//设置网格背景颜色
plot.setBackgroundPaint(Color.white);
//设置网格竖线颜色
plot.setDomainGridlinePaint(Color.pink);
//设置网格横线颜色
plot.setRangeGridlinePaint(Color.pink);
//显示每个柱的数值,并修改该数值的字体属性
BarRenderer3D renderer = new BarRenderer3D();
renderer.setBaseItemLabelGenerator(new StandardCategoryItemLabelGenerator());
renderer.setBaseItemLabelsVisible(true);
//默认的数字显示在柱子中,通过如下两句可调整数字的显示
//注意:此句很关键,若无此句,那数字的显示会被覆盖,给人数字没有显示出来的问题
renderer.setBasePositiveItemLabelPosition(new ItemLabelPosition(
ItemLabelAnchor.OUTSIDE12, TextAnchor.BASELINE_LEFT));
renderer.setItemLabelAnchorOffset(10D);
renderer.setItemLabelFont(new Font("宋体", Font.PLAIN, 12));
renderer.setItemLabelsVisible(true);
//设置每个地区所包含的平行柱的之间距离
//renderer.setItemMargin(0.3);
plot.setRenderer(renderer);
//设置地区、销量的显示位置
//将下方的“肉类”放到上方
plot.setDomainAxisLocation(AxisLocation.TOP_OR_RIGHT);
//将默认放在左边的“销量”放到右方
plot.setRangeAxisLocation(AxisLocation.BOTTOM_OR_RIGHT);
String filename = ServletUtilities.saveChartAsPNG(chart, 700, 400,
null, session);
String graphURL = request.getContextPath()
+ "/servlet/DisplayChart?filename=" + filename;
%>
<img src="<%=graphURL%>" width=700 height=400 border=0
usemap="#<%=filename%>">
步骤3,在你的web.xml中添加如下代码:
<servlet>
<servlet-name>DisplayChart</servlet-name>
<servlet-class>org.jfree.chart.servlet.DisplayChart</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>DisplayChart</servlet-name>
<url-pattern>/servlet/DisplayChart</url-pattern>
</servlet-mapping>