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    <p>The <a href="http://www.jfree.org/jfreechart/" rel="noreferrer"><code>JFreeChart</code></a> class <a href="http://www.jfree.org/jfreechart/api/javadoc/org/jfree/data/time/DynamicTimeSeriesCollection.html" rel="noreferrer"><code>DynamicTimeSeriesCollection</code></a> is a good choice.</p> <p>Addendum: As noted by @Bahadır, the last point of the series was persistently zero. @Don helpfully suggests advancing the time and <em>then</em> appending the data.</p> <pre><code>dataset.advanceTime(); dataset.appendData(newData); </code></pre> <p><img src="https://i.stack.imgur.com/dKHVg.png" alt="enter image description here"></p> <pre><code>import java.awt.BorderLayout; import java.awt.EventQueue; import java.awt.FlowLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.Random; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JPanel; import javax.swing.Timer; 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.DynamicTimeSeriesCollection; import org.jfree.data.time.Second; import org.jfree.data.xy.XYDataset; import org.jfree.ui.ApplicationFrame; import org.jfree.ui.RefineryUtilities; /** @see http://stackoverflow.com/questions/5048852 */ public class DTSCTest 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 DTSCTest(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); timer = new Timer(FAST, new ActionListener() { float[] newData = new float[1]; @Override public void actionPerformed(ActionEvent e) { newData[0] = randomValue(); dataset.advanceTime(); dataset.appendData(newData); } }); } private float randomValue() { return (float) (random.nextGaussian() * MINMAX / 3); } private float[] gaussianData() { float[] a = new float[COUNT]; for (int i = 0; i &lt; a.length; i++) { a[i] = randomValue(); } 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() { DTSCTest demo = new DTSCTest(TITLE); demo.pack(); RefineryUtilities.centerFrameOnScreen(demo); demo.setVisible(true); demo.start(); } }); } } </code></pre>
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    1. POUsing JFreeChart to display recent changes in a time series
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    1. COThanks for this great sample. Do you know a way to prevent the last point of the line to be at zero?
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    2. CO@Bahadır: It appears to be an intentional effect of `advanceTime()`. I've never had a use case for a different baseline value. Any thoughts? Don't forget to up-vote answers you found useful. :-)
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    3. CO"You last voted on this answer Apr 25 at 13:11" I always do. By the way, I fixed this by using TimeSeriesCollection instead of the dynamic one. Then replaced dataset.appendData with add, and setting a life time for the dataset. It gives pretty much the same functionality.
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