求JAVA GUI高手帮忙，谢谢！！

Question

我是个ＪＡＶＡ初学者，请教各位用ＧＵＩ建立直角坐标系的实时数据采集，画出曲线图怎么做？最好能有原代码，.cn谢谢大家

Answer 1

import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.time.Millisecond;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.ui.RectangleInsets;public class MemoryUsageDemo extends JPanel
{
private TimeSeries total; private TimeSeries free; public MemoryUsageDemo(int historyCount)
{
super(new BorderLayout());
this.total = new TimeSeries("Total Memory", Millisecond.class);
this.free = new TimeSeries("Free Memory", Millisecond.class);
this.total.setMaximumItemAge(30000);
this.free.setMaximumItemAge(30000);
TimeSeriesCollection dataset = new TimeSeriesCollection();
dataset.addSeries(total);
dataset.addSeries(free);
DateAxis domain = new DateAxis("Time");
NumberAxis range = new NumberAxis("Memory");
domain.setTickLabelFont(new Font("SansSerif", Font.PLAIN, 12));
range.setTickLabelFont(new Font("SansSerif", Font.PLAIN, 12));
domain.setLabelFont(new Font("SensSerif", Font.PLAIN, 14));
range.setLabelFont(new Font("SansSerif", Font.PLAIN, 14));
XYItemRenderer renderer = new XYLineAndShapeRenderer(true, false);
renderer.setSeriesPaint(0, Color.red);
renderer.setSeriesPaint(1, Color.green);
renderer.setStroke(new BasicStroke(3f, BasicStroke.CAP_BUTT,
BasicStroke.JOIN_BEVEL));
XYPlot plot = new XYPlot(dataset, domain, range, renderer);
plot.setBackgroundPaint(Color.lightGray);
plot.setDomainGridlinePaint(Color.white);
plot.setRangeGridlinePaint(Color.white);
plot.setAxisOffset(new RectangleInsets(5.0, 5.0, 5.0, 5.0));
domain.setAutoRange(true);
domain.setLowerMargin(0.0);
domain.setUpperMargin(0.0);
domain.setTickLabelsVisible(true);
range.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
JFreeChart chart = new JFreeChart("JVM Memory Usage", new Font(
"SansSerif", Font.BOLD, 24), plot, true);
chart.setBackgroundPaint(Color.white);
ChartPanel chartPanel = new ChartPanel(chart);
chartPanel.setBorder(BorderFactory.createCompoundBorder(BorderFactory
.createEmptyBorder(4, 4, 4, 4), BorderFactory
.createLineBorder(Color.black)));
add(chartPanel);
}
private void addTotalObservation(double y)
{
this.total.add(new Millisecond(),y);
}
private void addFreeObservation(double y)
{
this.free.add(new Millisecond(),y);
}
class DataGenerator extends Timer implements ActionListener
{
DataGenerator(int interval)
{
super(interval,null);
addActionListener(this);
}
public void actionPerformed(ActionEvent event)
{
long f=Runtime.getRuntime().freeMemory();
long t=Runtime.getRuntime().totalMemory();
addTotalObservation(t);
addFreeObservation(f);
}
}
public static void main(String[] args)
{
JFrame frame=new JFrame("Memory Usage Demo");
MemoryUsageDemo panel=new MemoryUsageDemo(30000);
frame.getContentPane().add(panel,BorderLayout.CENTER);
frame.setBounds(200,120,600,280);
frame.setVisible(true);
panel.new DataGenerator(100).start();
frame.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
}类中的org.jfree包中的类需要到down 一个jfree的jiar包添加到classpath中，然后运行。

Answer 2

地址在这里http://www.jfree.org/jfreechart/
上面的类是实时监视CPU的使用情况