svgexportdemo.java

在软件开发中用来绘制各种图表的源码

/* ------------------
 * SVGExportDemo.java
 * ------------------
 * (C) Copyright 2002-2005, by Object Refinery Limited.
 *
 */

package demo.svg;

import java.awt.geom.Rectangle2D;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;

import org.apache.batik.dom.GenericDOMImplementation;
import org.apache.batik.svggen.SVGGraphics2D;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.data.general.DefaultPieDataset;
import org.w3c.dom.DOMImplementation;
import org.w3c.dom.Document;

/** 
 * A demonstration showing the export of a chart to SVG format. 
 */
public class SVGExportDemo {

    /** 
     * Starting point for the demo. 
     * 
     * @param args ignored. 
     */
    public static void main(String[] args) throws IOException {
        
        // create a dataset... 
        DefaultPieDataset data = new DefaultPieDataset();
        data.setValue("Category 1", new Double(43.2));
        data.setValue("Category 2", new Double(27.9));
        data.setValue("Category 3", new Double(79.5));
        
        // create a chart 
        JFreeChart chart = ChartFactory.createPieChart(
            "Sample Pie Chart", 
            data, 
            true, 
            false, 
            false
        ); 
        
        // THE FOLLOWING CODE BASED ON THE EXAMPLE IN THE BATIK DOCUMENTATION... 
        // Get a DOMImplementation 
        DOMImplementation domImpl 
            = GenericDOMImplementation.getDOMImplementation(); 
        
        // Create an instance of org.w3c.dom.Document 
        Document document = domImpl.createDocument(null, "svg", null); 
        
        // Create an instance of the SVG Generator 
        SVGGraphics2D svgGenerator = new SVGGraphics2D(document);
        
        // set the precision to avoid a null pointer exception in Batik 1.5
        svgGenerator.getGeneratorContext().setPrecision(6);
         
        // Ask the chart to render into the SVG Graphics2D implementation 
        chart.draw(svgGenerator, new Rectangle2D.Double(0, 0, 400, 300), null); 
        
        // Finally, stream out SVG to a file using UTF-8 character to 
        // byte encoding 
        boolean useCSS = true; 
        Writer out = new OutputStreamWriter( 
            new FileOutputStream(new File("test.svg")), "UTF-8"); 
        svgGenerator.stream(out, useCSS); 
        
    } 

}