在java中使用jfree图表制作动态折线图

如何使用java中的jFree图表创建动态折线图，该图表显示2小时前的数据，并且还提供一个空白区域，数据显示从当前时间开始2小时。例如假设当前时间是下午4点，因此图表显示数据从下午2点到下午6点。下午2点到下午4点，图表显示一条线，下午4点到下午6点提供一个空白区域，填充图表移动的时间，这意味着该图形的尾部从中间开始向右移动。 类似于股市图表。

Answer 1

是的，你可以做到。 几天前我遇到了类似的问题。

DynamicLineAndTimeSeriesChart.java

import java.awt.BorderLayout; import java.awt.Color; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.Timer; import javax.swing.JPanel; 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; import org.jfree.data.xy.XYDataset; import org.jfree.ui.ApplicationFrame; import org.jfree.ui.RefineryUtilities; /** * An example to show how we can create a dynamic chart. */ public class DynamicLineAndTimeSeriesChart extends ApplicationFrame implements ActionListener { /** The time series data. */ private TimeSeries series; /** The most recent value added. */ private double lastValue = 100.0; /** Timer to refresh graph after every 1/4th of a second */ private Timer timer = new Timer(250, this); /** * Constructs a new dynamic chart application. * * @param title the frame title. */ public DynamicLineAndTimeSeriesChart(final String title) { super(title); this.series = new TimeSeries("Random Data", Millisecond.class); final TimeSeriesCollection dataset = new TimeSeriesCollection(this.series); final JFreeChart chart = createChart(dataset); timer.setInitialDelay(1000); //Sets background color of chart chart.setBackgroundPaint(Color.LIGHT_GRAY); //Created JPanel to show graph on screen final JPanel content = new JPanel(new BorderLayout()); //Created Chartpanel for chart area final ChartPanel chartPanel = new ChartPanel(chart); //Added chartpanel to main panel content.add(chartPanel); //Sets the size of whole window (JPanel) chartPanel.setPreferredSize(new java.awt.Dimension(800, 500)); //Puts the whole content on a Frame setContentPane(content); timer.start(); } /** * Creates a sample chart. * * @param dataset the dataset. * * @return A sample chart. */ private JFreeChart createChart(final XYDataset dataset) { final JFreeChart result = ChartFactory.createTimeSeriesChart( "Dynamic Line And TimeSeries Chart", "Time", "Value", dataset, true, true, false ); final XYPlot plot = result.getXYPlot(); plot.setBackgroundPaint(new Color(0xffffe0)); plot.setDomainGridlinesVisible(true); plot.setDomainGridlinePaint(Color.lightGray); plot.setRangeGridlinesVisible(true); plot.setRangeGridlinePaint(Color.lightGray); ValueAxis xaxis = plot.getDomainAxis(); xaxis.setAutoRange(true); //Domain axis would show data of 60 seconds for a time xaxis.setFixedAutoRange(60000.0); // 60 seconds xaxis.setVerticalTickLabels(true); ValueAxis yaxis = plot.getRangeAxis(); yaxis.setRange(0.0, 300.0); return result; } /** * Generates an random entry for a particular call made by time for every 1/4th of a second. * * @param e the action event. */ public void actionPerformed(final ActionEvent e) { final double factor = 0.9 + 0.2*Math.random(); this.lastValue = this.lastValue * factor; final Millisecond now = new Millisecond(); this.series.add(new Millisecond(), this.lastValue); System.out.println("Current Time in Milliseconds = " + now.toString()+", Current Value : "+this.lastValue); } /** * Starting point for the dynamic graph application. * * @param args ignored. */ public static void main(final String[] args) { final DynamicLineAndTimeSeriesChart demo = new DynamicLineAndTimeSeriesChart("Dynamic Line And TimeSeries Chart"); demo.pack(); RefineryUtilities.centerFrameOnScreen(demo); demo.setVisible(true); } } 

另请查看：

http://blog.odoobiz.com/2012/07/how-to-draw-dynamic-line-or-timeseries.html