Java使用icepdf将pdf文件按页转成图片

<dependency> <groupId>org.icepdf.os</groupId> <artifactId>icepdf-core</artifactId> <version>6.1.2</version>  <exclusions>  <exclusion>   <groupId>javax.media</groupId>   <artifactId>jai-core</artifactId>  </exclusion> </exclusions></dependency>

import java.awt.image.BufferedImage;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.text.DecimalFormat;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import java.util.Map;import javax.imageio.IIOImage;import javax.imageio.ImageIO;import javax.imageio.ImageWriter;import javax.imageio.stream.ImageOutputStream;import org.apache.commons.logging.LogFactory;import org.icepdf.core.exceptions.PDFException;import org.icepdf.core.exceptions.PDFSecurityException;import org.icepdf.core.pobjects.Document;import org.icepdf.core.pobjects.Page;import org.icepdf.core.util.GraphicsRenderingHints;public class test20160929 { public static final String FILETYPE_JPG = "jpg"; /**  *   * 将指定的pdf文件转换为指定路径的图片  *   * @param filepath 原文件路径，例如d:/test/test.pdf  *   * @param imagepath 图片生成路径，例如 d:/test/  *   * @param zoom 缩略图显示倍数，1表示不缩放，0.3则缩小到30%  *   */ public static void tranfer(String filepath, String imagepath, float zoom) throws PDFException, PDFSecurityException, IOException {  Document document = null;  float rotation = 0f;  document = new Document();  document.setFile(filepath);  int maxPages = document.getPageTree().getNumberOfPages();  for (int i = 0; i < maxPages; i++) {   BufferedImage img = (BufferedImage) document.getPageImage(i, GraphicsRenderingHints.SCREEN, Page.BOUNDARY_CROPBOX, rotation, zoom);   Iterator iter = ImageIO.getImageWritersBySuffix(FILETYPE_JPG);   ImageWriter writer = (ImageWriter) iter.next();   File outFile = new File(imagepath + new File(filepath).getName() + "_" + new DecimalFormat("000").format(i) + "." + FILETYPE_JPG);   FileOutputStream out = new FileOutputStream(outFile);   ImageOutputStream outImage = ImageIO.createImageOutputStream(out);   writer.setOutput(outImage);   writer.write(new IIOImage(img, null, null));  }  System.out.println("转换完成"); } public static void main(String[] args) throws PDFException, PDFSecurityException, IOException {  tranfer("d:/test/test.pdf", "d:/test/", 1); }}