JFreeChart氣泡圖表

本章演示如何使用JFreeChart從一個給定的業務數據創建氣泡圖表。使用氣泡圖顯示在三維方式的信息。氣泡繪製在其中(x，y)座標相交的地方。氣泡的大小被認爲是範圍或X和Y軸的數量。

業務數據

考慮不同的人的年齡，體重和工作能力可能不太相同。能力可以視爲對該被繪製爲圖表中的氣泡的小時數。

WEIGHT

AGE

 

30

40

50

60

70

80

 

10

4

 

 

 

 

 

WORK

20

 

5

 

 

 

 

30

 

 

10

 

 

 

40

 

 

 

8

 

 

50

 

 

 

 

9

 

60

 

 

 

 

 

6

基於AWT的應用

以下是對從上述給定的信息創建氣泡圖表的代碼。此代碼可以幫助嵌入一個氣泡圖在AWT應用程序。

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 ); } }

讓我們保存上面的Java代碼在BubbleChart_AWT.java文件，然後從命令提示符下編譯並運行它，如下所示：

$javac BubbleChart_AWT.java
$java BubbleChart_AW

如果一切順利，它會編譯並運行生成以下氣泡圖：

創建JPEG圖像

讓我們重新編寫上面的例子，在命令行生成JPEG圖像。

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); } }

讓我們保存上面的Java代碼在BubbleChart_image.java文件，然後從命令提示符下編譯並運行它，如下所示：

$javac BubbleChart_image.java
$java BubbleChart_image

如果一切順利，它會編譯並運行在當前的目錄中創建的JPEG圖像文件namedBubbleChart.jpeg。