jFreeChart利用CategoryDatase,ChartFactory.createBarChart生成的柱状图

Createjfreechartbar 代码  

1. package com.potevio.rnd;  
2.   
3. import java.io.File;  
4. import java.io.FileNotFoundException;  
5. import java.io.FileOutputStream;  
6. import java.io.IOException;  
7.   
8. import org.jfree.chart.ChartFactory;  
9. import org.jfree.chart.ChartUtilities;  
10. import org.jfree.chart.JFreeChart;  
11. import org.jfree.chart.plot.CategoryPlot;  
12. import org.jfree.chart.plot.PlotOrientation;  
13. import org.jfree.data.category.CategoryDataset;  
14. import org.jfree.data.general.DatasetUtilities;  
15.   
16. public class CreateJFreeChartBar {     
17.     
18.     /**    
19.      * 创建JFreeChart Bar Chart（柱状图）    
20.      */    
21.     public static void main(String[] args) {     
22.         //步骤1：创建CategoryDataset对象（准备数据）     
23.         CategoryDataset dataset = createDataset();     
24.         //步骤2：根据Dataset 生成JFreeChart对象，以及做相应的设置     
25.         JFreeChart freeChart = createChart(dataset);     
26.         //步骤3：将JFreeChart对象输出到文件，Servlet输出流等     
27.         saveAsFile(freeChart, "F:\jfreechart\bar.png", 500, 400);     
28.     }     
29.          
30.     //保存为文件     
31.     public static void saveAsFile(JFreeChart chart, String outputPath, int weight, int height) {     
32.         FileOutputStream out = null;     
33.         try {     
34.             File outFile = new File(outputPath);     
35.             if (!outFile.getParentFile().exists()) {     
36.                 outFile.getParentFile().mkdirs();     
37.             }     
38.             out = new FileOutputStream(outputPath);     
39.             //保存为PNG文件     
40.             ChartUtilities.writeChartAsPNG(out, chart, weight, height);     
41.             //保存为JPEG文件     
42.             //ChartUtilities.writeChartAsJPEG(out, chart, weight, height);     
43.             out.flush();     
44.         } catch (FileNotFoundException e) {     
45.             e.printStackTrace();     
46.         } catch (IOException e) {     
47.             e.printStackTrace();     
48.         } finally {     
49.             if (out != null) {     
50.                 try {     
51.                     out.close();     
52.                 } catch (IOException e) {     
53.                     //do nothing     
54.                 }     
55.             }     
56.         }     
57.     }     
58.     
59.     //根据CategoryDataset生成JFreeChart对象     
60.     public static JFreeChart createChart(CategoryDataset categoryDataset) {     
61.         JFreeChart jfreechart = ChartFactory.createBarChart("Bar Chart Demo",    //标题     
62.                 "产品",    //categoryAxisLabel （category轴，横轴，X轴的标签）     
63.                 "数量",    //valueAxisLabel（value轴，纵轴，Y轴的标签）     
64.                 categoryDataset, // dataset     
65.                 PlotOrientation.VERTICAL,     
66.                 true, // legend     
67.                 false, // tooltips     
68.                 false); // URLs     
69.              
70.         //以下的设置可以由用户定制，也可以省略     
71.         CategoryPlot  plot = (CategoryPlot) jfreechart.getPlot();     
72.         //背景色　透明度     
73.         plot.setBackgroundAlpha(0.5f);     
74.         //前景色　透明度     
75.         plot.setForegroundAlpha(0.5f);     
76.         //其它设置可以参考 CategoryPlot     
77.              
78.         return jfreechart;     
79.     }     
80.     
81.     /**    
82.      * 创建CategoryDataset对象    
83.      *     
84.      */    
85.     public static CategoryDataset createDataset() {     
86.              
87.         String []rowKeys = {"One", "Two", "Three"};     
88.         String []colKeys = {"1987", "1997", "2007"};     
89.              
90.         double [][] data = {     
91.                 {50, 20, 30},     
92.                 {20, 10D, 40D},     
93.                 {40, 30.0008D, 38.24D},     
94.         };     
95.              
96.         //也可以使用以下代码     
97.         //DefaultCategoryDataset categoryDataset = new DefaultCategoryDataset();     
98.         //categoryDataset.addValue(10, "rowKey", "colKey");     
99.              
100.         return DatasetUtilities.createCategoryDataset(rowKeys, colKeys, data);             
101.     }     
102.     
103. }  

package com.potevio.rnd;
import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;
import org.jfree.chart.ChartFactory;

import org.jfree.chart.ChartUtilities;

import org.jfree.chart.JFreeChart;

import org.jfree.chart.plot.CategoryPlot;

import org.jfree.chart.plot.PlotOrientation;

import org.jfree.data.category.CategoryDataset;

import org.jfree.data.general.DatasetUtilities;
public class CreateJFreeChartBar {
/**  
 * 创建JFreeChart Bar Chart（柱状图）  
 */  
public static void main(String[] args) {   
    //步骤1：创建CategoryDataset对象（准备数据）   
    CategoryDataset dataset = createDataset();   
    //步骤2：根据Dataset 生成JFreeChart对象，以及做相应的设置   
    JFreeChart freeChart = createChart(dataset);   
    //步骤3：将JFreeChart对象输出到文件，Servlet输出流等   
    saveAsFile(freeChart, "F:\jfreechart\bar.png", 500, 400);   
}   
   
//保存为文件   
public static void saveAsFile(JFreeChart chart, String outputPath, int weight, int height) {   
    FileOutputStream out = null;   
    try {   
        File outFile = new File(outputPath);   
        if (!outFile.getParentFile().exists()) {   
            outFile.getParentFile().mkdirs();   
        }   
        out = new FileOutputStream(outputPath);   
        //保存为PNG文件   
        ChartUtilities.writeChartAsPNG(out, chart, weight, height);   
        //保存为JPEG文件   
        //ChartUtilities.writeChartAsJPEG(out, chart, weight, height);   
        out.flush();   
    } catch (FileNotFoundException e) {   
        e.printStackTrace();   
    } catch (IOException e) {   
        e.printStackTrace();   
    } finally {   
        if (out != null) {   
            try {   
                out.close();   
            } catch (IOException e) {   
                //do nothing   
            }   
        }   
    }   
}   

//根据CategoryDataset生成JFreeChart对象   
public static JFreeChart createChart(CategoryDataset categoryDataset) {   
    JFreeChart jfreechart = ChartFactory.createBarChart("Bar Chart Demo",    //标题   
            "产品",    //categoryAxisLabel （category轴，横轴，X轴的标签）   
            "数量",    //valueAxisLabel（value轴，纵轴，Y轴的标签）   
            categoryDataset, // dataset   
            PlotOrientation.VERTICAL,   
            true, // legend   
            false, // tooltips   
            false); // URLs   
       
    //以下的设置可以由用户定制，也可以省略   
    CategoryPlot  plot = (CategoryPlot) jfreechart.getPlot();   
    //背景色　透明度   
    plot.setBackgroundAlpha(0.5f);   
    //前景色　透明度   
    plot.setForegroundAlpha(0.5f);   
    //其它设置可以参考 CategoryPlot   
       
    return jfreechart;   
}   

/**  
 * 创建CategoryDataset对象  
 *   
 */  
public static CategoryDataset createDataset() {   
       
    String []rowKeys = {"One", "Two", "Three"};   
    String []colKeys = {"1987", "1997", "2007"};   
       
    double [][] data = {   
            {50, 20, 30},   
            {20, 10D, 40D},   
            {40, 30.0008D, 38.24D},   
    };   
       
    //也可以使用以下代码   
    //DefaultCategoryDataset categoryDataset = new DefaultCategoryDataset();   
    //categoryDataset.addValue(10, "rowKey", "colKey");   
       
    return DatasetUtilities.createCategoryDataset(rowKeys, colKeys, data);           
}   

}

运行效果图：