createlinemodel.java

本程序主要是实现了JFreeChart的图形显示！

package com.kai.jfc;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.NumberFormat;
import java.text.SimpleDateFormat;
import java.util.TimeZone;

import javax.servlet.http.HttpSession;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartRenderingInfo;
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.axis.PeriodAxis;
import org.jfree.chart.axis.PeriodAxisLabelInfo;
import org.jfree.chart.entity.StandardEntityCollection;
import org.jfree.chart.labels.StandardXYToolTipGenerator;
import org.jfree.chart.plot.IntervalMarker;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.chart.servlet.ServletUtilities;
import org.jfree.chart.title.TextTitle;
import org.jfree.data.time.Day;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.data.xy.XYDataset;
import org.jfree.ui.Layer;
import org.jfree.ui.RectangleAnchor;
import org.jfree.ui.RectangleInsets;
import org.jfree.ui.TextAnchor;

/**
 * 类文件：CreateLineUtil.java
 * @author 作者: 王凯 E-mail: [e-mail]
 * @version 创建时间：Sep 9, 2008 2:08:44 PM
 * 类 CreateLineUtil 的作用：
 */

public class CreateLineModel {
	/**
	    * 本方法是创建JFreeChart的图表格式和设置图表的各种属性
	    * @param session 是将创建好的图表做为IO流放在Session中，
	    * 				  在页面中获取Session中的图片IO流打印在网页上
	    * @param pw
	    * @return
	    */
		public String getLineXYChart(HttpSession session, PrintWriter pw) 
		{
			XYDataset dataset = this.createDateSet();// 建立数据集
			String fileName = null;
			// 建立JFreeChart
			JFreeChart chart = ChartFactory.createTimeSeriesChart("JFreeChart时间曲线序列图", // title
								"Date", //   x轴上的标签
								"Price", //  y轴上的标签
								dataset, // data
								true, // create legend?
								true, // generate tooltips?
								false // generate URLs?
								);
		   // 设置JFreeChart的显示属性,对图形外部部分进行调整
		   chart.setBackgroundPaint(Color.WHITE);// 设置曲线图背景色
		   // 设置字体大小，形状
		   Font font = new Font("宋体", Font.BOLD, 16);
		   TextTitle title = new TextTitle("JFreeChart时间曲线序列图", font);
		   chart.setTitle(title);
		
		   XYPlot plot = (XYPlot) chart.getPlot(); //获取图形的画布
		   plot.setBackgroundPaint(Color.WHITE);   //设置网格背景色
		   plot.setDomainGridlinePaint(Color.GRAY); //设置网格竖线(Domain轴)颜色
		   plot.setRangeGridlinePaint(Color.GRAY); //设置网格横线颜色
		   plot.setAxisOffset(new RectangleInsets(5.0, 5.0, 5.0, 5.0)); //设置曲线图与xy轴的距离
		   plot.setDomainCrosshairVisible(true);
		   plot.setRangeCrosshairVisible(true);
		   
		   XYItemRenderer r = plot.getRenderer();
		   if (r instanceof XYLineAndShapeRenderer) 
		   {
			   XYLineAndShapeRenderer renderer = (XYLineAndShapeRenderer) r;
			   // renderer.setDefaultShapesVisible(true);
			   // renderer.setDefaultShapesFilled(true);
			   renderer.setShapesFilled(true);
			   renderer.setShapesVisible(true);// 设置曲线是否显示数据点
		   }
		
		   // 设置Y轴
		   NumberAxis numAxis = (NumberAxis) plot.getRangeAxis();
		   NumberFormat numFormater = NumberFormat.getNumberInstance();
		   numFormater.setMinimumFractionDigits(2);
		   numAxis.setNumberFormatOverride(numFormater);
		
		   // 设置提示信息
		   StandardXYToolTipGenerator tipGenerator = new StandardXYToolTipGenerator("({1},{2})", new SimpleDateFormat("yyyy年MM月dd日"), numFormater);
		   r.setBaseToolTipGenerator(tipGenerator);
		
		   // 设置X轴（日期轴）
		   DateAxis axis = (DateAxis) plot.getDomainAxis();
		   axis.setDateFormatOverride(new SimpleDateFormat("yyyy年MM"));
		   
		   ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
		   try 
		   {
			   fileName = ServletUtilities.saveChartAsPNG(chart, 500, 300, info,session);// 生成图片
			   // Write the image map to the PrintWriter
			   ChartUtilities.writeImageMap(pw, fileName, info, false);
		   } catch (IOException e) {
			   e.printStackTrace();
		   }
		   pw.flush();
		   this.savejpg(chart, "F:/bar.jpg"); 
		   return fileName;// 返回生成图片的文件名
		}
		/**
		 * 建立生成图形所需的数据集
		 * @return 返回数据集
		 */
		private XYDataset createDateSet()
		{
			TimeSeriesCollection dataset = new TimeSeriesCollection();// 时间曲线数据集合
			TimeSeries s1 = new TimeSeries("历史曲线", Day.class);// 创建时间数据源，每一个//TimeSeries在图上是一条曲线

			// s1.add(new Day(day,month,year),value),添加数据点信息
			s1.add(new Day(1, 2, 2006), 123.51);
			s1.add(new Day(2, 2, 2006), 122.1);
			s1.add(new Day(3, 2, 2006), 120.86);
			s1.add(new Day(4, 2, 2006), 122.50);
			s1.add(new Day(5, 2, 2006), 123.12);
			s1.add(new Day(6, 2, 2006), 123.9);
			s1.add(new Day(7, 2, 2006), 124.47);
			s1.add(new Day(8, 2, 2006), 124.08);
			s1.add(new Day(9, 2, 2006), 123.55);
			s1.add(new Day(10, 2, 2006), 122.53);
//			Comparable
			TimeSeries s2 = new TimeSeries("历史曲线", Day.class);// 创建时间数据源，每一个//TimeSeries在图上是一条曲线

			// s1.add(new Day(day,month,year),value),添加数据点信息
			s2.add(new Day(1, 2, 2006), 120.51);
			s2.add(new Day(2, 2, 2006), 120.1);
			s2.add(new Day(3, 2, 2006), 125.86);
			s2.add(new Day(4, 2, 2006), 123.50);
			s2.add(new Day(5, 2, 2006), 120.12);
			s2.add(new Day(6, 2, 2006), 127.9);
			s2.add(new Day(7, 2, 2006), 121.47);
			s2.add(new Day(8, 2, 2006), 125.08);
			s2.add(new Day(9, 2, 2006), 120.55);
			s2.add(new Day(10, 2, 2006), 121.53);
			
			dataset.addSeries(s1);
			dataset.addSeries(s2);
			//dataset.setDomainIsPointsInTime(true);
			return dataset;
		}
		 //保存为本地图片    
	    private void savejpg(JFreeChart chart,String jpgname)    
	    {    
	        FileOutputStream jpg = null;    
	        try {    
	            jpg = new FileOutputStream(jpgname);    
	            ChartUtilities.writeChartAsJPEG(jpg,0.5f,chart,800,500,null);    
	                
	        } catch (Exception e) {    
	            // TODO 自动生成 catch 块    
	            e.printStackTrace();    
	        }    
	        finally   
	        {    
	            try {    
	                jpg.close();    
	            } catch (IOException e) {    
	                // TODO 自动生成 catch 块    
	                e.printStackTrace();    
	            }    
	        }    
	    }
}