文件名包含特殊字符的Java Spring Boot下载文件会生成零字节的下载文件

import org.springframework.util.StreamUtils;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLDecoder;
import java.nio.charset.StandardCharsets;

@RestController
public class FileDownloadController {

    @GetMapping("/download/{fileName}")
    public void downloadFile(@PathVariable String fileName, HttpServletResponse response) throws IOException {
        // 解码文件名
        String decodedFileName = URLDecoder.decode(fileName, StandardCharsets.UTF_8);

        // 获取文件路径
        String filePath = "/path/to/files/" + decodedFileName;

        File file = new File(filePath);
        if (file.exists()) {
            // 设置响应头
            response.setContentType("application/octet-stream");
            response.setHeader("Content-Disposition", "attachment; filename=\"" + decodedFileName + "\"");
            response.setContentLength((int) file.length());

            // 读取文件并写入响应流
            try (InputStream inputStream = new FileInputStream(file)) {
                StreamUtils.copy(inputStream, response.getOutputStream());
            }
        } else {
            // 文件不存在，返回错误信息
            response.setStatus(HttpServletResponse.SC_NOT_FOUND);
            response.getWriter().write("File not found.");
        }
    }
}