摘要：基于轉換的電子書閱讀插件部分項目一般都是以插件閱讀文件，但存在閱讀體驗不理想的情況，所以參考手機上的電子書閱讀器，使用國外的鏈接描述制作電子書示例。

項目一般都是以pdf.js插件閱讀PDF文件，但存在閱讀體驗不理想的情況，所以參考手機上的電子書閱讀器，使用國外的鏈接描述http://fliphtml5.com
制作電子書示例。

完整代碼已上傳git，標題搜索即可。

插件功能強大，縮略圖，鼠標翻頁，放大縮小都可以，部分配置代碼config.js如下

var bookConfig = {
    appName:"flippdf",
    totalPageCount : 0,
    largePageWidth : 1080,
    largePageHeight : 1440,
    normalPath : "files/page/",
    largePath : "files/large/",
    thumbPath : "files/thumb/",
    
    ToolBarsSettings:"",
    TitleBar:"",
    appLogoLinkURL:"",
    bookTitle:"FLIPBUILDER",
    bookDescription:"",
    ButtonsBar:"",
    ShareButton:"",
    
    ThumbnailsButton:"",
    ThumbnailsButtonVisible:"Hide",
    ZoomButton:"",
    ZoomButtonVisible:"No",
    FlashDisplaySettings:"",
    MainBgConfig:"",
    bgBeginColor:"#cccccc",
    bgEndColor:"#eeeeee",
    bgMRotation:45,
    pageBackgroundColor:"#FFFFFF",
    flipshortcutbutton:"Hide",
    BookMargins:"",
    topMargin:10,
    bottomMargin:10,
    leftMargin:10,
    rightMargin:10,
    HTMLControlSettings:"",
    linkconfig:"",
    LinkDownColor:"#808080",
    LinkAlpha:0.5,
    OpenWindow:"_Blank",

    BookMarkButtonVisible:"False",
    productName : "Demo created by Flip PDF",
    homePage : "http://www.html5.com/",
    isFlipPdf : "False",
    TableOfContentButtonVisible:"False",
    searchTextJS:"javascript/search_config.js",
    searchPositionJS:undefined
};

插件顯示實際是使用的jpg圖片，可以由pdf文檔生成，其中涉及的是正常圖片和縮略圖的生成。
具體如下

maven引入

            org.apache.pdfbox
            fontbox
            2.0.9
        
        
            org.apache.pdfbox
            pdfbox
            2.0.9
        

核心程序

import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;


public class pdftest {
    public static void main(String[] args) {
        String fileAddress="D:data";
        String filename="qqq";
        String type="jpg";
        pdf2png(fileAddress,filename,type);
    }
     /**
     * 轉換全部的pdf
     * @param fileAddress 文件地址
     * @param filename PDF文件名
     * @param type 圖片類型
     */
    public static void pdf2png(String fileAddress,String filename,String type) {
        // 將pdf裝圖片 并且自定義圖片得格式大小
        File file = new File(fileAddress+""+filename+".pdf");
        try {
            PDDocument doc = PDDocument.load(file);
            PDFRenderer renderer = new PDFRenderer(doc);
            int pageCount = doc.getNumberOfPages();
            for (int i = 0; i < pageCount; i++) {
                BufferedImage image = renderer.renderImageWithDPI(i, 144); // Windows native DPI
          
                //ImageIO.write(image, type, new File(fileAddress+""+filename+"_"+(i+1)+"."+type));
                ImageIO.write(image, type, new File("D:datahtml5-ebook-paging-mobilefilesmobile"+(i+1)+"."+type));
                
                BufferedImage srcImage = resize(image, 240, 240);//產生縮略圖
                ImageIO.write(srcImage, type, new File("D:datahtml5-ebook-paging-mobilefiles	humb"+(i+1)+"."+type));//產生縮略圖
                
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
 
 
/**
     *自由確定起始頁和終止頁
     * @param fileAddress 文件地址
     * @param filename pdf文件名
     * @param indexOfStart 開始頁  開始轉換的頁碼，從0開始
     * @param indexOfEnd 結束頁  停止轉換的頁碼，-1為全部
     * @param type 圖片類型
     */
    public static void pdf2png(String fileAddress,String filename,int indexOfStart,int indexOfEnd,String type) {
        // 將pdf裝圖片 并且自定義圖片得格式大小
        File file = new File(fileAddress+""+filename+".pdf");
        try {
            PDDocument doc = PDDocument.load(file);
            PDFRenderer renderer = new PDFRenderer(doc);
            int pageCount = doc.getNumberOfPages();
            for (int i = indexOfStart; i < indexOfEnd; i++) {
                BufferedImage image = renderer.renderImageWithDPI(i, 144); // Windows native DPI
                // BufferedImage srcImage = resize(image, 240, 240);//產生縮略圖
                ImageIO.write(image, type, new File(fileAddress+""+filename+"_"+(i+1)+"."+type));
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    /**
     * 縮略圖
     */
    private static BufferedImage resize(BufferedImage source, int targetW, int targetH) {    
        int type = source.getType();        
        BufferedImage target = null;
        double sx = (double) targetW / source.getWidth();
        double sy = (double) targetH / source.getHeight();
        if (sx > sy) {            
            sx = sy;
            targetW = (int) (sx * source.getWidth());
        } else 
        {            
            sy = sx;
            targetH = (int) (sy * source.getHeight());        
        }
        if (type == BufferedImage.TYPE_CUSTOM) {
            ColorModel cm = source.getColorModel();    
            WritableRaster raster = cm.createCompatibleWritableRaster(targetW, targetH);
            boolean alphaPremultiplied = cm.isAlphaPremultiplied();            
            target = new BufferedImage(cm, raster, alphaPremultiplied, null);    
            } else {
             target = new BufferedImage(targetW, targetH, type);        
        }    
        Graphics2D g = target.createGraphics();        
        g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);    
        g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy));        
        g.dispose();        
        return target;    
        }
}