转载自 JFreeChart气泡图表
本章演示如何使用JFreeChart从一个给定的业务数据创建气泡图表。使用气泡图显示在三维方式的信息。气泡绘制在其中(x，y)坐标相交的地方。气泡的大小被认为是范围或X和Y轴的数量。
业务数据
考虑不同的人的年龄，体重和工作能力可能不太相同。能力可以视为对该被绘制为图表中的气泡的小时数。
| WEIGHT | ||||||||
|---|---|---|---|---|---|---|---|---|
| AGE | 30 | 40 | 50 | 60 | 70 | 80 | ||
| 10 | 4 | WORK | ||||||
| 20 | 5 | |||||||
| 30 | 10 | |||||||
| 40 | 8 | |||||||
| 50 | 9 | |||||||
| 60 | 6 | |||||||
基于AWT的应用
以下是对从上述给定的信息创建气泡图表的代码。此代码可以帮助嵌入一个气泡图在AWT应用程序。
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JPanel;
import org.jfree.chart.*;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.data.xy.DefaultXYZDataset;
import org.jfree.data.xy.XYZDataset;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RefineryUtilities;public class BubbleChart_AWT extends ApplicationFrame
{public BubbleChart_AWT( String s ){super( s ); JPanel jpanel = createDemoPanel( ); jpanel.setPreferredSize(new Dimension( 560 , 370 ) ); setContentPane( jpanel ); }private static JFreeChart createChart( XYZDataset xyzdataset ){JFreeChart jfreechart = ChartFactory.createBubbleChart("AGE vs WEIGHT vs WORK", "Weight", "AGE", xyzdataset, PlotOrientation.HORIZONTAL, true, true, false);XYPlot xyplot = ( XYPlot )jfreechart.getPlot( ); xyplot.setForegroundAlpha( 0.65F ); XYItemRenderer xyitemrenderer = xyplot.getRenderer( );xyitemrenderer.setSeriesPaint( 0 , Color.blue ); NumberAxis numberaxis = ( NumberAxis )xyplot.getDomainAxis( ); numberaxis.setLowerMargin( 0.2 ); numberaxis.setUpperMargin( 0.5 ); NumberAxis numberaxis1 = ( NumberAxis )xyplot.getRangeAxis( ); numberaxis1.setLowerMargin( 0.8 ); numberaxis1.setUpperMargin( 0.9 );return jfreechart;}public static XYZDataset createDataset( ){DefaultXYZDataset defaultxyzdataset = new DefaultXYZDataset(); double ad[ ] = { 30 , 40 , 50 , 60 , 70 , 80 }; double ad1[ ] = { 10 , 20 , 30 , 40 , 50 , 60 }; double ad2[ ] = { 4 , 5 , 10 , 8 , 9 , 6 }; double ad3[][] = { ad , ad1 , ad2 }; defaultxyzdataset.addSeries( "Series 1" , ad3 );return defaultxyzdataset; }public static JPanel createDemoPanel( ){JFreeChart jfreechart = createChart( createDataset( ) ); ChartPanel chartpanel = new ChartPanel( jfreechart );chartpanel.setDomainZoomable( true ); chartpanel.setRangeZoomable( true );return chartpanel;}public static void main( String args[ ] ){BubbleChart_AWT bubblechart = new BubbleChart_AWT( "Bubble Chart_frame" ); bubblechart.pack( ); RefineryUtilities.centerFrameOnScreen( bubblechart ); bubblechart.setVisible( true ); }
}让我们保存上面的Java代码在BubbleChart_AWT.java文件，然后从命令提示符下编译并运行它，如下所示：
$javac BubbleChart_AWT.java $java BubbleChart_AW
如果一切顺利，它会编译并运行生成以下气泡图：
创建JPEG图像
让我们重新编写上面的例子，在命令行生成JPEG图像。
import java.io.*;
import java.awt.Color;
import org.jfree.chart.*;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.data.xy.DefaultXYZDataset;
import org.jfree.chart.ChartUtilities;public class BubbleChart_image
{public static void main( String args[ ] )throws Exception{DefaultXYZDataset defaultxyzdataset = new DefaultXYZDataset( );double ad[ ] = { 30 , 40 , 50 , 60 , 70 , 80 };double ad1[ ] = { 10 , 20 , 30 , 40 , 50 , 60 };double ad2[ ] = { 4 , 5 , 10 , 8 , 9 , 6 };double ad3[ ][ ] = { ad , ad1 , ad2 };defaultxyzdataset.addSeries( "Series 1" , ad3 );JFreeChart jfreechart = ChartFactory.createBubbleChart("AGE vs WEIGHT vs WORK", "Weight", "AGE", defaultxyzdataset, PlotOrientation.HORIZONTAL, true, true, false);XYPlot xyplot = ( XYPlot )jfreechart.getPlot( );xyplot.setForegroundAlpha( 0.65F );XYItemRenderer xyitemrenderer = xyplot.getRenderer( );xyitemrenderer.setSeriesPaint( 0 , Color.blue );NumberAxis numberaxis = ( NumberAxis )xyplot.getDomainAxis( );numberaxis.setLowerMargin( 0.2 );numberaxis.setUpperMargin( 0.5 );NumberAxis numberaxis1 = ( NumberAxis )xyplot.getRangeAxis( );numberaxis1.setLowerMargin( 0.8 );numberaxis1.setUpperMargin( 0.9 );int width = 560; /* Width of the image */int height = 370; /* Height of the image */ File bubbleChart = new File("BubbleChart.jpeg"); ChartUtilities.saveChartAsJPEG(bubbleChart,jfreechart,width,height);}
}让我们保存上面的Java代码在BubbleChart_image.java文件，然后从命令提示符下编译并运行它，如下所示：
$javac BubbleChart_image.java $java BubbleChart_image
如果一切顺利，它会编译并运行在当前的目录中创建的JPEG图像文件namedBubbleChart.jpeg。
