动态 JFreeChart 时间序列

Question

[编辑] 基于这个example，我是now able来收集数据并显示在图表中。我不知道如何将生成图表的代码集成到我的应用程序中。

/** @see http://stackoverflow.com/questions/5048852 */
public class Atol extends ApplicationFrame {

private static final String TITLE = "Dynamic Series";
private static final String START = "Start";
private static final String STOP = "Stop";
private static final float MINMAX = 100;
private static final int COUNT = 2 * 60;
private static final int FAST = 100;
private static final int SLOW = FAST * 5;
private static final Random random = new Random();
private Timer timer;

public Atol(final String title) {
    super(title);
    final DynamicTimeSeriesCollection dataset
            = new DynamicTimeSeriesCollection(1, COUNT, new Second());
    dataset.setTimeBase(new Second(0, 0, 0, 1, 1, 2011));
    dataset.addSeries(gaussianData(), 0, "Gaussian data");
    JFreeChart chart = createChart(dataset);

    final JButton run = new JButton(STOP);
    run.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            String cmd = e.getActionCommand();
            if (STOP.equals(cmd)) {
                timer.stop();
                run.setText(START);
            } else {
                timer.start();
                run.setText(STOP);
            }
        }
    });

    final JComboBox combo = new JComboBox();
    combo.addItem("Fast");
    combo.addItem("Slow");
    combo.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            if ("Fast".equals(combo.getSelectedItem())) {
                timer.setDelay(FAST);
            } else {
                timer.setDelay(SLOW);
            }
        }
    });
   this.add(new ChartPanel(chart), BorderLayout.CENTER);
   JPanel btnPanel = new JPanel(new FlowLayout());
   btnPanel.add(run);
    btnPanel.add(combo);
    this.add(btnPanel, BorderLayout.SOUTH);
    SystemInfo si = new SystemInfo();             //Criando uma nova classe de infos do Sistem
    HardwareAbstractionLayer hal = si.getHardware(); //Infos de Hardware do sistema
    CentralProcessor cpu = hal.getProcessor();      //E as informações da cpu
    long[] oldTricks = cpu.getSystemCpuLoadTicks();

    
    timer = new Timer(FAST, new ActionListener() {
        float cpu() {

            Double stats = cpu.getSystemCpuLoadBetweenTicks(oldTricks);
            //Convertendo o valor de uso da CPU
            stats = stats * 100d;
            double teste = Math.round(stats * 100.0) / 100.0;
            double d = teste;
            float f = (float) d;
            System.out.println(f);
            return f;
        }
        float[] newData = new float[1];

        @Override
        public void actionPerformed(ActionEvent e) {

            newData[0] = cpu();
            dataset.advanceTime();
            dataset.appendData(newData);
        }
    });
}


private float[] gaussianData() {

    float[] a = new float[COUNT];
    for (int i = 0; i < a.length; i++) {
        a[i] = 2;
    }
    return a;
}

private JFreeChart createChart(final XYDataset dataset) {
    final JFreeChart result = ChartFactory.createTimeSeriesChart(
            TITLE, "hh:mm:ss", "milliVolts", dataset, true, true, false);
    final XYPlot plot = result.getXYPlot();
    ValueAxis domain = plot.getDomainAxis();
    domain.setAutoRange(true);
    ValueAxis range = plot.getRangeAxis();
    range.setRange(-MINMAX, MINMAX);
    return result;
}

public void start() {
    timer.start();
}

public static void main(final String[] args) {
    EventQueue.invokeLater(new Runnable() {

        @Override
        public void run() {
           Atol demo = new Atol(TITLE);
            demo.pack();

            demo.setVisible(true);
            demo.start();
        }
    });
}

}

致我的JFrame 代码（在另一个类中）：

   private void kButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    // when I click in that button
    
    Atol demo = new Atol ("");       
   chartCPU.add(new ChartPanel(demo)); //Thats the JPanel the chart need to appear and readjust to it size

}

如果JFreeChart 在一个构造函数中，我如何在 Atol 类中调用图表（JFreeChart 图表）？我没有得到！ 我怎样才能让它出现在我的chartCPUJPanel 中？ （这是一个名为TelaLogin 的JFrame 类，与Atol 类不同）。

Answer 1

您的original question 询问如何捕获 CPU 数据并将其显示在图表中。由于相关方法的延迟较低，因此可以在javax.swing.Timer 的动作监听器中调用该方法，如here 及以上所示。

具有不可预测延迟的数据访问可能会阻塞event dispatch thread，在这种情况下，您应该改用SwingWorker，如here 所示。

要将图表集成到您的应用程序中，请将示例的构造函数重构为工厂方法并采用以下方法之一：

• CardLayout，显示为here。

• JTabbedPane，显示为here。

• JInternalFrame，显示为here 和here。