Jfreechart+ajax 实现动态仪表图 java代码

package demo;

import java.awt.Color;
import java.awt.Font;
import java.awt.GradientPaint;
import java.awt.Point;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URISyntaxException;

import org.jfree.chart.ChartUtilities;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.dial.DialBackground;
import org.jfree.chart.plot.dial.DialCap;
import org.jfree.chart.plot.dial.DialPlot;
import org.jfree.chart.plot.dial.DialTextAnnotation;
import org.jfree.chart.plot.dial.DialValueIndicator;
import org.jfree.chart.plot.dial.StandardDialFrame;
import org.jfree.chart.plot.dial.StandardDialRange;
import org.jfree.chart.plot.dial.StandardDialScale;
import org.jfree.data.general.DefaultValueDataset;
import org.jfree.ui.GradientPaintTransformType;
import org.jfree.ui.StandardGradientPaintTransformer;

public class Dial {
	public static String getDial(String warnName,String warnValueStr) {
		double warnValue;
		try{
			double tempDouble = Double.valueOf(warnValueStr);
			warnValue =tempDouble;
		}catch(Exception ex){
			ex.printStackTrace();
			warnValue=0;
		}
		
		DefaultValueDataset dataset = new DefaultValueDataset();
		dataset = new DefaultValueDataset(warnValue);
		DialPlot dialplot = new DialPlot();
		dialplot.setView(0.0D, 0.0D, 1.0D, 1.0D);
		dialplot.setDataset(dataset);
		
		StandardDialFrame simpledialframe = new StandardDialFrame();
		simpledialframe.setBackgroundPaint(Color.lightGray);
		simpledialframe.setForegroundPaint(Color.darkGray);
		dialplot.setDialFrame(simpledialframe);
		
		GradientPaint gradientpaint = new GradientPaint(new Point(),Color.lightGray, new Point(),Color.GRAY);
		
		DialBackground dialbackground = new DialBackground(gradientpaint);
		dialbackground.setGradientPaintTransformer(new StandardGradientPaintTransformer(GradientPaintTransformType.VERTICAL));
		dialplot.setBackground(dialbackground);
		dialplot.setBackgroundPaint(Color.CYAN);
		DialTextAnnotation dialtextannotation = new DialTextAnnotation(warnName);
		dialtextannotation.setFont(new Font("宋体", 1, 16));
		dialtextannotation.setPaint(Color.black);
		dialtextannotation.setRadius(0.69999999999999996D);
		dialplot.addLayer(dialtextannotation);
		

		if(warnValue==0){
			StandardDialRange standarddialrange2 = new StandardDialRange(0D, 100D,Color.cyan);
			standarddialrange2.setInnerRadius(0.52000000000000002D);
			standarddialrange2.setOuterRadius(1);
			dialplot.addLayer(standarddialrange2);	
		}else if(warnValue>0&&warnValue<=100){
		StandardDialRange standarddialrange1 = new StandardDialRange(0D, 100D,Color.yellow);
		standarddialrange1.setInnerRadius(0.52000000000000002D);
		standarddialrange1.setOuterRadius(1);
		dialplot.addLayer(standarddialrange1);
		}else if(warnValue>100&&warnValue<=1000){
			StandardDialRange standarddialrange = new StandardDialRange(0D, 1000D,new Color(251,57,36));
			standarddialrange.setInnerRadius(0.52000000000000002D);
			standarddialrange.setOuterRadius(1);
			dialplot.addLayer(standarddialrange);
		}else if(warnValue>1000){		
			StandardDialRange standarddialrange = new StandardDialRange(0D, 10000D,Color.red);
			standarddialrange.setInnerRadius(0.52000000000000002D);
			standarddialrange.setOuterRadius(1);
			dialplot.addLayer(standarddialrange);
		}
		
		
		DialValueIndicator dialvalueindicator = new DialValueIndicator(0);
		dialvalueindicator.setFont(new Font("宋体", 1, 14));		
		dialvalueindicator.setPaint(Color.cyan);
		dialvalueindicator.setOutlinePaint(Color.lightGray);
		dialvalueindicator.setBackgroundPaint(Color.GRAY);
		dialvalueindicator.setRadius(0.39999999999999998D);
		//dialvalueindicator.setPaint(Color.red);
		dialplot.addLayer(dialvalueindicator);

		
		double startPosition=0D; //开度 0
        double endPosition=100D; //开度 100
        double skipValue=10D; //间隔 10
       
        if(warnValue>100&&warnValue<1000){
           endPosition=1000D;
           skipValue=100D;
        }else if(warnValue>=1000){
            endPosition=10000D;
            skipValue=1000D;
        }
        //刻度盘设置
		StandardDialScale standarddialscale = new StandardDialScale(startPosition, endPosition,-120D, -300D, skipValue, 4);
		standarddialscale.setTickRadius(0.88D);//设置半径
		standarddialscale.setTickLabelOffset(0.14999999999999999D);
		standarddialscale.setTickLabelFont(new Font("Dialog", 0, 10));//刻度盘数字大小

		// 注意是 dialplot.addScale（）不是dialplot.addLayer（）
		dialplot.addScale(0, standarddialscale);


		// 设置指针
		org.jfree.chart.plot.dial.DialPointer.Pointer pointer = new org.jfree.chart.plot.dial.DialPointer.Pointer();
		pointer.setFillPaint(Color.red);
		pointer.setOutlinePaint(Color.red);
		pointer.setRadius(0.75D);
		dialplot.addLayer(pointer);

		// 实例化DialCap
		DialCap dialcap = new DialCap();
		dialcap.setRadius(0.10000000000000001D);
		dialplot.setCap(dialcap);

		// 生成chart对象
		JFreeChart jfreechart = new JFreeChart(dialplot);

		// 3、设定参数输出结果,首先在 项目/WEB-INF/classes/,添加WarnImages文件夹
		String filePath="";//绝对路径
		//String webPath="WarnImages/"+System.currentTimeMillis()+".jpeg";//动态文件名 相对
		String webPath="WarnImages/meter.jpeg";
		try {
			filePath = Thread.currentThread().getContextClassLoader().getResource("").toURI().getPath();
			filePath =filePath.replace("WEB-INF/classes/", "");
			filePath += webPath;
			System.out.println(filePath);
		} catch (URISyntaxException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}

	        
		FileOutputStream file = null;
		try {
			file = new FileOutputStream(filePath);
			ChartUtilities.writeChartAsJPEG(file, 1.0f, jfreechart, 200, 200,null);//200,200 图片大小
			
		} catch (IOException e) {
			e.printStackTrace();
		} // 生成图片
		finally {
			try {
				file.close();// 最后关闭文件流
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return webPath;
	}

	public static void main(String[] args) {
		//System.out.println(new Dial().getDial("测试","366"));
		System.out.println(String.valueOf(randomNum()));
		System.out.println(new Dial().getDial("测试",String.valueOf(randomNum())));
	}
	
	private static int  randomNum()   
	{      
	        System.out.println((int)(Math.random()*60+300));         
	        return (int)(Math.random()*60+80);   
	} 
}


package demo;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.sinoufc.nms.mon.rmi.RMIClient;

public class DialServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public DialServlet() {
		
		super();
	}

	 public void service(HttpServletRequest request, HttpServletResponse response)   
     throws ServletException, IOException {   
		 int memoryUsedRate = 0;
	        try
	        {
	        	//memoryUsedRate = RMIClient.getRMIInterface().getInFlow("10.10..9.188",1);
	        	//memoryUsedRate = RMIClient.getRMIInterface().getInFlow("111", 1);
	        	System.out.println("memoryUsedRate="+memoryUsedRate);
	        }
	        catch(Exception ex)
	        {
	        	ex.printStackTrace();
	        }
	       // System.out.println(new Dial().getDial("测试",String.valueOf(memoryUsedRate)));
	        System.out.println(Dial.getDial("测试",String.valueOf(randomNum())));
	 }
	
	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	private static int  randomNum()   
	{      
	        System.out.println((int)(Math.random()*60+300));         
	        return (int)(Math.random()*60+80);   
	}  

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}