获取Springboot 项目中resource目录中的文件

工具类代码如下

public File readFile(String filename) {
    try {
        // 获取资源文件的输入流
        URL resourceUrl = ResourceReader.class.getResource(filename);
        if (resourceUrl == null) {
            throw new RuntimeException("resourceUrl is null");
        }

        // 将资源文件内容读取到临时文件
        return createTempFileFromResource(resourceUrl);
    } catch (IOException e) {
        log.error("读取资源文件出错", e);
        throw new RuntimeException(e);
    }
}

private File createTempFileFromResource(URL resourceUrl) throws IOException {
    try (InputStream is = resourceUrl.openStream()) {
        File tempFile = File.createTempFile("temp", ".txt");
        FileOutputStream fos = new FileOutputStream(tempFile);
        byte[] buffer = new byte[1024];
        int length;
        while ((length = is.read(buffer)) > 0) {
            fos.write(buffer, 0, length);
        }
        fos.close();
        return tempFile;
    }
}