pdf转图片（qq:2798641729）

前面已经把html转成pdf，但是用户可以下载图片格式的文件，所以我们必须把pdf转成图片格式，代码如下

package com.jit.platform.basics.util.pdf;

import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.util.ArrayList;
import java.util.List;

import javax.imageio.ImageIO;

import org.jpedal.PdfDecoder;

class ImgPp{
    BufferedImage img;
    int width ;
    int height;
    public BufferedImage getImg() {
        return img;
    }
    public void setImg(BufferedImage img) {
        this.img = img;
    }
    public int getWidth() {
        return width;
    }
    public void setWidth(int width) {
        this.width = width;
    }
    public int getHeight() {
        return height;
    }
    public void setHeight(int height) {
        this.height = height;
    } 

}

public class PdfToImg {

    public static List<String> toImgList(String pdfPath,String imgPath,String imgName) throws Exception{

        PdfDecoder decode_pdf = new PdfDecoder(true);
        decode_pdf.openPdfFile(pdfPath); //file
        int start = 1, end = decode_pdf.getPageCount();

        List<String> list = new ArrayList<String>();
        for(int i=start;i<end+1;i++){
            BufferedImage img=decode_pdf.getPageAsImage(i);
            String fileName = imgPath + imgName+"_"+i +".png";
            ImageIO.write(img, "png", new File(fileName));
            list.add(fileName);
        }
        decode_pdf.closePdfFile();

        return list;

    }

    public static String toImgOne(String pdfPath,String imgPath,String imgName) throws Exception {        

        PdfDecoder decode_pdf = new PdfDecoder(true);
        decode_pdf.openPdfFile(pdfPath); //file
        int start = 1, end = decode_pdf.getPageCount();

        List<ImgPp> list = new ArrayList<ImgPp>();
        int width = 0;
        int totalHeight = 0;
        for(int i=start;i<end+1;i++){
            BufferedImage img=decode_pdf.getPageAsImage(i);
            ImgPp imgpp = new ImgPp();
            imgpp.setImg(img);
            imgpp.setWidth(img.getWidth());
            imgpp.setHeight(img.getHeight());
            totalHeight+=img.getHeight();
            width=img.getWidth();
            list.add(imgpp);
        }

        String mergeImage = mergeImage(list ,totalHeight,width ,imgPath,imgName);

        decode_pdf.closePdfFile();

        return mergeImage;

    }  

     public static String mergeImage(List<ImgPp> list,int totalHeight,int width,String imgPath,String imgName) throws Exception {  

            //构造一个类型为预定义图像类型之一的 BufferedImage。 宽度为第一只的宽度，高度为各个图片高度之和
             BufferedImage tag = new BufferedImage(width, totalHeight, BufferedImage.TYPE_INT_RGB);
             //绘制合成图像
            Graphics g = tag.createGraphics(); 

            int tempHeight = 0;
             for (int i = 0; i < list.size(); i++) {
                 ImgPp imgPp = list.get(i);
                 g.drawImage(imgPp.getImg(), 0, tempHeight, width, imgPp.getHeight(), null);
                 tempHeight+=imgPp.getHeight();
            }
             // 释放此图形的上下文以及它使用的所有系统资源。
             g.dispose();  

             // Save as new image
            ImageIO.write(tag, "png", new File(imgPath + imgName));
            return imgName;  

        } 
    public static void main(String[] args) {

        String pdfPath = "D:\\many page.pdf";
        String imgPath = "D:\\";
        String imgName = "pdfbox_image";
        try {
            String imgOne = toImgOne(pdfPath,imgPath,imgName);
            System.out.println("imgOne"+imgOne);

            /*List<String> img2 = toImgList(pdfPath,imgPath,imgName);

            File[] fileArray = new File[img2.size()];
            for (int i = 0; i < img2.size(); i++) {
                //System.out.println(img2.get(i));
                File file = new File(img2.get(i));
                fileArray[i] = file;
            }
            BatchDownloadAction.makeZip(imgPath,imgName , fileArray);*/

        } catch (Exception e1) {
            e1.printStackTrace();
        }

    }

}

项目中遇到了用户还可以下载图片格式的文件，所以我们就需要把pdf转成图片，下面是我们完成的代码。