JFreeChart中文显示问题_柱状图

CODE：

<%@ page contentType="text/html;charset=GBK"%>
<%@ page language="java" pageEncoding="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.DefaultCategoryDataset,
                org.jfree.data.category.CategoryDataset,
                org.jfree.data.general.DatasetUtilities,
                java.awt.Color,
                java.awt.Font,
                org.jfree.chart.block.*,
                org.jfree.chart.plot.*,
                org.jfree.chart.axis.*,
                org.jfree.chart.title.LegendTitle,
                org.jfree.data.general.DefaultPieDataset,
                org.jfree.data.general.PieDataset,
                org.jfree.ui.*,
                org.jfree.chart.labels.StandardPieSectionLabelGenerator,
                java.text.DecimalFormat,
                java.text.NumberFormat,
                org.jfree.chart.title.TextTitle    
                "%> 
 
<%
	DefaultCategoryDataset dataset = new DefaultCategoryDataset();
	dataset.addValue(610, "广州", "猪肉");
	dataset.addValue(220, "广州", "牛肉");
	dataset.addValue(530, "广州", "鸡肉");
	dataset.addValue(340, "广州", "鱼肉");
	
	JFreeChart chart = ChartFactory.createBarChart3D("肉类销量统计图", 
	                  "肉类",
	                  "销量",
	                  dataset,
	                  PlotOrientation.VERTICAL,
	                  false,
	                  false,
	                  false);
	
	chart.getTitle().setFont(new Font("隶书", Font.ITALIC, 20));//设置标题    
	chart.setBackgroundPaint(Color.white); //设定背景色为白色
	CategoryPlot categoryPlot=chart.getCategoryPlot();//获得 plot,用于设置显示特性  
	
    categoryPlot.setBackgroundPaint(Color.WHITE);  
    categoryPlot.setDomainGridlinePaint(Color.BLACK);//分类轴网格线条颜色  
    categoryPlot.setDomainGridlinesVisible(true);  
    categoryPlot.setRangeGridlinePaint(Color.GREEN);//数据轴网格线条颜色  
    
    //图表的字体设置
    CategoryAxis domainAxis=categoryPlot.getDomainAxis(); //水平底部列表   
    domainAxis.setLabelFont(new Font("楷体",Font.BOLD,14)); //X轴标题   
    domainAxis.setTickLabelFont(new Font("宋体",Font.BOLD,12)); //x轴下标  
    
    ValueAxis rangeAxis=categoryPlot.getRangeAxis();//获取柱状   
    rangeAxis.setLabelFont(new Font("楷体",Font.BOLD,14)); //Y轴标题 
	
	
	/*
	categoryplot.setBackgroundPaint(Color.lightGray); //设定图表数据显示部分背景色
	categoryplot.setDomainGridlinePaint(Color.white); //横坐标网格线白色
	categoryplot.setDomainGridlinesVisible(true); //可见
	categoryplot.setRangeGridlinePaint(Color.white); //纵坐标网格线白色
	*/
	
	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 %>">

运行结果：