利用java，把SQL SERVER數據庫裏面的書庫繪制成圖表的形式，類似於股票那樣有XY軸，曲線顯示，怎麽做啊？

有兩種實現方式，壹種就是JFreeChart的官方實例MemoryUsageDemo.java.通過壹個實現java.Swing.Timer的內部類，在其監聽器中將實時數據添加進TimeSeries，由於Timer是會實時執行的，所以這個方法倒是沒有什麽問題，可以參考代碼。

另壹種方式就是將實時類實現Runnable接口，在其run()方法中，通過無限循環將實時數據添加進TimeSeries，下面是較簡單的實現代碼：

java 代碼

//RealTimeChart .java

import org.jfree.chart.ChartFactory;

import org.jfree.chart.ChartPanel;

import org.jfree.chart.JFreeChart;

import org.jfree.chart.axis.ValueAxis;

import org.jfree.chart.plot.XYPlot;

import org.jfree.data.time.Millisecond;

import org.jfree.data.time.TimeSeries;

import org.jfree.data.time.TimeSeriesCollection;

public class RealTimeChart extends ChartPanel implements Runnable

{

private static TimeSeries timeSeries;

private long value=0;

public RealTimeChart(String chartContent,String title,String yaxisName)

{

super(createChart(chartContent,title,yaxisName));

}

private static JFreeChart createChart(String chartContent,String title,String yaxisName){

//創建時序圖對象

timeSeries = new TimeSeries(chartContent,Millisecond.class);

TimeSeriesCollection timeseriescollection = new TimeSeriesCollection(timeSeries);

JFreeChart jfreechart = ChartFactory.createTimeSeriesChart(title,"時間(秒)",yaxisName,timeseriescollection,true,true,false);

XYPlot xyplot = jfreechart.getXYPlot();

//縱坐標設定

ValueAxis valueaxis = xyplot.getDomainAxis();

//自動設置數據軸數據範圍

valueaxis.setAutoRange(true);

//數據軸固定數據範圍 30s

valueaxis.setFixedAutoRange(30000D);

valueaxis = xyplot.getRangeAxis();

//valueaxis.setRange(0.0D,200D);

return jfreechart;

}

public void run()

{

while(true)

{

try

{

timeSeries.add(new Millisecond(), randomNum());

Thread.sleep(300);

}

catch (InterruptedException e) { }

}

}

private long randomNum()

{

System.out.println((Math.random()*20+80));

return (long)(Math.random()*20+80);

}

}

//Test.java

import java.awt.BorderLayout;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import javax.swing.JFrame;

public class Test

{

/**

* @param args

*/

public static void main(String[] args)

{

JFrame frame=new JFrame("Test Chart");

RealTimeChart rtcp=new RealTimeChart("Random Data","隨機數","數值");

frame.getContentPane().add(rtcp,new BorderLayout().CENTER);

frame.pack();

frame.setVisible(true);

(new Thread(rtcp)).start();

frame.addWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent windowevent)

{

System.exit(0);

}

});

}

}

這兩中方法都有壹個問題，就是每實現壹個圖就要重新寫壹次，因為實時數據無法通過參數傳進來，在想有沒有可能通過setXXX()方式傳進實時數據，那樣的話就可以將實時曲線繪制類封裝起來，而只需傳遞些參數即可。