Docx4j PDF转换中页眉页脚临时图片残留问题解析与规避

import org.docx4j.Docx4J;
import org.docx4j.convert.out.FOSettings;
import org.docx4j.convert.out.fo.renderers.FORendererApacheFOP;
import org.docx4j.fonts.Mapper;
import org.docx4j.fonts.BestMatchingMapper;
import org.docx4j.openpackaging.packages.WordprocessingMLPackage;
import org.apache.fop.apps.FopFactory;
import org.apache.fop.apps.FopFactoryBuilder;
import org.apache.fop.apps.FOUserAgent;
import org.apache.commons.io.FileUtils; // 需要引入Apache Commons IO库

import java.io.File;
import java.io.OutputStream;

public class DocxToPdfConverter {

    private static final String TEMP_IMAGE_DIR_PATH = "/tmp/images"; // 自定义临时图片目录

    public static void convert(WordprocessingMLPackage wordMLPackage, OutputStream output) throws Exception {

        // 1. 设置字体映射
        Mapper fontMapper = new BestMatchingMapper();
        wordMLPackage.setFontMapper(fontMapper);

        // 2. 配置FOSettings
        FOSettings foSettings = new FOSettings(wordMLPackage);
        foSettings.setApacheFopMime("application/pdf"); // 指定输出MIME类型为PDF
        foSettings.setImageDirPath(TEMP_IMAGE_DIR_PATH); // 设置自定义图片临时目录
        foSettings.setFoDumpFile(null); // 不生成FO调试文件

        // 3. 构建FopFactory和FOUserAgent
        FopFactoryBuilder fopFactoryBuilder = FORendererApacheFOP.getFopFactoryBuilder(foSettings);
        FopFactory fopFactory = fopFactoryBuilder.build();
        FOUserAgent foUserAgent = FORendererApacheFOP.getFOUserAgent(foSettings, fopFactory);

        // 4. 执行转换
        Docx4J.toFO(foSettings, output, Docx4J.FLAG_EXPORT_PREFER_XSL);

        // 5. 清理临时文件
        // 清理可能由ObfuscatedFontPart生成的临时字体文件
        if (wordMLPackage.getMainDocumentPart().getFontTablePart() != null) {
            wordMLPackage.getMainDocumentPart().getFontTablePart().deleteEmbeddedFontTempFiles();
        }

        // 6. 释放资源
        foSettings = null;
        wordMLPackage = null;

        // 7. 尝试删除自定义临时图片目录
        // 注意：此操作仅删除foSettings.setImageDirPath()指定的目录中的文件
        // 无法删除页眉/页脚图片在/tmp中生成的临时文件
        try {
            File tempImageDir = new File(TEMP_IMAGE_DIR_PATH);
            if (tempImageDir.exists() && tempImageDir.isDirectory()) {
                FileUtils.deleteDirectory(tempImageDir);
                System.out.println("自定义临时图片目录已清理: " + TEMP_IMAGE_DIR_PATH);
            }
        } catch (Exception e) {
            System.err.println("清理自定义临时图片目录失败: " + e.getMessage());
        }
    }
}