1、饼状图：
 DefaultPieDataset dataset=new DefaultPieDataset();//填充饼状图的数据 集合
 ConnectionProvider cp=((SessionFactoryImplementor)this.lgispEquipmentService.getEntityDao().getHibernateTemplate().getSessionFactory()).getConnectionProvider();
    try{
//sql 语句
 String pointSql=" select count(*) as count,point.point_type from lgisp_point as point , lgisp_equipment as equip, lgisp_terminal as ter  where point.equipment_id=equip.EQUIPMENT_ID and equip.terminal_id=ter.terminal_id group by point.point_type";
     Statement smt=cp.getConnection().createStatement();
     ResultSet rs=smt.executeQuery(pointSql);//查询获得结果集
      double equipCount=0;//设备总数目
      HashMap hashMap=new HashMap();
     while(rs.next()){
      double count=Double.parseDouble(rs.getString(1));
      int type=Integer.parseInt(rs.getString(2));
      equipCount+=count;
      hashMap.put(type, count);
     }
     List<TerManuFacturer> equipManuList=(List<TerManuFacturer>) request.getSession().getAttribute("pointManuList");
     for(TerManuFacturer equip:equipManuList){
      double rate=Double.parseDouble((hashMap.get(equip.getId())).toString())/ equipCount;
            dataset.setValue(equip.getManuName(), rate);
     }// 以上的代码是为生成图的dataset 准备数据

     //通过工厂类生成JFreeChart对象
     JFreeChart chart=ChartFactory.createPieChart("设备——厂家分配图", dataset, true, false, false);
     PiePlot piePlot=(PiePlot)chart.getPlot();
     //防止乱码，多标题重新设备字体（乱码问题借鉴http://chengyue2007.iteye.com/blog/424954 得到解决）
     TextTitle textTitle=chart.getTitle();
     textTitle.setFont(new Font("黑体",Font.PLAIN,20));
     piePlot.setLabelFont(new Font("宋体",0,12));  
     //没有数据时显示的内容
     piePlot.setNoDataMessage("无数据显示");
     piePlot.setCircular(false);
     piePlot.setLabelGap(0.02D);
     OutputStream ostream=response.getOutputStream();
     ChartUtilities.writeChartAsJPEG(ostream, chart,500, 500);
     ostream.flush();
     ostream.close();
    return "输出图的页面";

2、柱状图
 DefaultCategoryDataset dataset = new DefaultCategoryDataset(); 
 ConnectionProvider cp =((SessionFactoryImplementor)this.reportService.getEntityDao().getHibernateTemplate().getSessionFactory()).getConnectionProvider();
  try{
   Statement smt = cp.getConnection().createStatement();
   ResultSet rs = smt.executeQuery("sql 语句);
   while(rs.next()){    
    dataset.addValue(Double.parseDouble(rs.getString(1)),rs.getString(2), "") ;
   }
     JFreeChart chart = ChartFactory.createBarChart3D( 
             "图标测试", // 图表标题 
             "班级", // 目录轴的显示标签 
             "分数", // 数值轴的显示标签 
             dataset, // 数据集 
             PlotOrientation.VERTICAL, // 图表方向：水平、垂直 
             true, // 是否显示图例(对于简单的柱状图必须是false) 
             false, // 是否生成工具 
             false // 是否生成URL链接 
             ); 
     OutputStream ostream = response.getOutputStream(); 
     //设定图片的宽为400,高为300,并输出至ostream      
     ChartUtilities.writeChartAsJPEG(ostream, chart, 800, 600); 
     ostream.flush(); 
     ostream.close(); 
    return"输出图的页面;