java 图片转PDF

package image;

import com.itextpdf.text.Document;
import com.itextpdf.text.Image;
import com.itextpdf.text.PageSize;
import com.itextpdf.text.pdf.PdfWriter;

import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

/**
 * 功能1：图片转PDF
 * 功能2：删除图片
 * 注意：转换pdf文件上限约20~30万
 */
public class ImgToPDF {
    private static int count = 0;
    private static final List<String> IMAGE_EXTENSIONS = Arrays.asList(".tif",".jpg", ".jpeg", ".png", ".gif", ".bmp"); // 支持的图片格式

    public static void main(String[] args) throws Exception {
        System.setProperty("itext.licensekey.disableagplwarning", "true");//个人用户引入itextpdf临时禁止不需要的提示。

        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        count = 0;
        System.out.println("任务开始：" + dateFormat.format(new Date()));

        String directoryPath = "F:\\数据转换\\11\\two";

        // 1、将子目录下所有图片转成PDF
        List<File> imageFiles = findImageFiles(directoryPath);
        int executors = Runtime.getRuntime().availableProcessors();
        int executorSize = 2 * executors;
        ExecutorService executor = Executors.newFixedThreadPool(executorSize);
        threadPool(imageFiles, executor);

        //2、删除子目录所有图片
        //findImagesInSubdirectories(directoryPath);
        System.out.println("任务结束：" + dateFormat.format(new Date()));
    }

    public static void threadPool(List<File> excelFilePaths, ExecutorService executor) {
        List<Callable<Void>> tasks = new ArrayList<>();
        // 将每个Excel文件的转换任务添加到列表中
        for (File file : excelFilePaths) {
            tasks.add(() -> {
                // 在这里实现img到PDF的转换逻辑
                boolean result = generatePdfFile(file);
                if (result) {
                    setFileRecord("\n\t文件已转换成功：" + file.getAbsolutePath() + "，已转"+count+"个");
                } else {
                    setFileRecord("\n\t文件已转换失败：" + file.getAbsolutePath() + "，已转"+count+"个");
                }
                return null;
            });
        }
        try {
            // 提交所有任务到线程池，并等待它们完成
            executor.invokeAll(tasks);
        } catch (InterruptedException e) {
            System.out.println("Interrupted while waiting for tasks to complete");
            Thread.currentThread().interrupt(); // 重新设置中断标志
        } finally {
            shutdownExecutor(executor);
        }
    }
    private static void shutdownExecutor(ExecutorService executor) {
        executor.shutdown();
        try {
            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {
                executor.shutdownNow();
                if (!executor.awaitTermination(60, TimeUnit.SECONDS))
                    System.out.println("Pool did not terminate");
            }
        } catch (InterruptedException ie) {
            executor.shutdownNow();
            Thread.currentThread().interrupt(); // 重新设置中断标志
        }
    }

    /**
     * 将图片转换为PDF文件
     */
    private static boolean generatePdfFile(File file) throws Exception {
        try {
            String fileName = file.getAbsolutePath();
            String pdfFileName = fileName.substring(0, fileName.lastIndexOf(".")) + ".pdf";
            Document doc = new Document(PageSize.A4, 20, 20, 20, 20);
            PdfWriter.getInstance(doc, new FileOutputStream(pdfFileName));
            doc.open();
            doc.newPage();
            Image image = Image.getInstance(file.getPath());
            float height = image.getHeight();
            float width = image.getWidth();
            int percent = getPercent(height, width);
            image.setAlignment(Image.MIDDLE);
            image.scalePercent(percent);
            doc.add(image);
            doc.close();
            File pdfFile = new File(pdfFileName);
            count++;
            System.out.println("File created: " + pdfFile.getAbsolutePath() + "，已转"+count+"个");
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return  false;
        }

    }

    /**
     * 等比压缩，获取压缩百分比
     *
     * @param height 图片的高度
     * @param weight 图片的宽度
     * @return 压缩百分比
     */
    private static int getPercent(float height, float weight) {
        float percent = 0.0F;
        if (height > weight) {
            percent = PageSize.A4.getHeight() / height * 100;
        } else {
            percent = PageSize.A4.getWidth() / weight * 100;
        }
        return Math.round(percent);
    }
    public static void findImagesInSubdirectories(String rootPath) throws Exception {
        File rootDirectory = new File(rootPath);
        File[] subDirectories = rootDirectory.listFiles(File::isDirectory); // 只获取子目录
        if (subDirectories != null) {
            for (File dir : subDirectories) {
                searchForImages(dir);
            }
        }
    }

    private static void searchForImages(File directory) throws Exception {
        File[] files = directory.listFiles((dir, name) -> {
            String lowerCaseName = name.toLowerCase();
            return IMAGE_EXTENSIONS.stream()
                    .anyMatch(lowerCaseName::endsWith);
        });
        if(files != null){
            processFiles(files);
        }
    }


    public static List<File> findImageFiles(String directoryPath) {
        List<File> imageFiles = new ArrayList<>();
        File directory = new File(directoryPath);

        if (directory.exists() && directory.isDirectory()) {
            File[] files = directory.listFiles();
            if (files!= null) {
                for (File file : files) {
                    if (file.isDirectory()) {
                        // 递归查找子目录中的图片文件
                        imageFiles.addAll(findImageFiles(file.getAbsolutePath()));
                    } else {
                        String fileName = file.getName();
                        int start = fileName.lastIndexOf(".");
                        int end = fileName.length();
                        String fileType = fileName.substring(start, end).toLowerCase();
                        if (IMAGE_EXTENSIONS.contains(fileType)) {
                              imageFiles.add(file);
                        }
                    }
                }
            }
        }
        return imageFiles;
    }

    public static void setFileRecord(String content){
        try {
            SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
            // 创建FileWriter对象，第二个参数true表示追加模式
            FileWriter writer = new FileWriter("imgToPdf"+ sdf.format(new Date())+".txt", true);
            //String content = "这是要追加到txt文件中的新内容";
            writer.write(content);
            writer.close();
            //System.out.println("内容已成功追加到文件中");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }


 
}