sample4.jsp

JFreeChart开发全攻略,JFreeChart开发全攻略

<%@ page contentType="text/html;charset=GBK"%>
<%@ 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"%>
<%
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("肉类销量统计图", 
                  "肉类",
                  "销量",
                  dataset,
                  PlotOrientation.VERTICAL,
                  true,
                  true,
                  false);

CategoryPlot plot = chart.getCategoryPlot();
//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);
//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() + "/DisplayChart?filename=" + filename;
%>
<img src="<%= graphURL %>" width=700 height=400 border=0 usemap="#<%= filename %>">