利用JFreeChart生成简单柱状图(Servlet)

 /* * To change this template, choose Tools | Templates * and open the template in the editor. */package servlet;import java.awt.Font;import java.io.IOException;import java.io.OutputStream;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.jfree.chart.ChartFactory;import org.jfree.chart.ChartUtilities;import org.jfree.chart.JFreeChart;import org.jfree.chart.axis.CategoryAxis;import org.jfree.chart.axis.NumberAxis;import org.jfree.chart.plot.CategoryPlot;import org.jfree.chart.plot.PlotOrientation;import org.jfree.data.category.CategoryDataset;import org.jfree.data.category.DefaultCategoryDataset;/** * * @author Administrator */public class BarChartServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("image/jpeg"); OutputStream out = response.getOutputStream(); CategoryDataset ds = getDataSet(); 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 ds, //数据集 PlotOrientation.VERTICAL, //图表方向 true, //是否显示图例，对于简单的柱状图必须为false false, //是否生成提示工具 false); //是否生成url链接 CategoryPlot categoryplot = (CategoryPlot) chart.getPlot(); NumberAxis numberaxis = (NumberAxis) categoryplot.getRangeAxis(); CategoryAxis domainAxis = categoryplot.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)); /*******这句代码解决了标题汉字乱码的问题********/ chart.getTitle().setFont(new Font("宋体", Font.PLAIN, 12)); try { ChartUtilities.writeChartAsJPEG(out, 0.5f, chart, 400, 300, null); } finally { try { out.close(); } catch (Exception ex) { ex.printStackTrace(); } } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } private CategoryDataset getDataSet() { DefaultCategoryDataset ds = new DefaultCategoryDataset(); ds.addValue(100, "北京", "苹果"); ds.addValue(100, "上海", "苹果"); ds.addValue(100, "广州", "苹果"); ds.addValue(200, "北京", "梨子"); ds.addValue(200, "上海", "梨子"); ds.addValue(200, "广州", "梨子"); ds.addValue(300, "北京", "葡萄"); ds.addValue(300, "上海", "葡萄"); ds.addValue(300, "广州", "葡萄"); ds.addValue(400, "北京", "橘子"); ds.addValue(400, "上海", "橘子"); ds.addValue(400, "广州", "橘子"); ds.addValue(500, "北京", "香蕉"); ds.addValue(500, "上海", "香蕉"); ds.addValue(500, "广州", "香蕉"); return ds; }}

 

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