文件下载OOM

File file = new File(filePath);// 几百兆的文件，直接拉到内存？byte[] data = Files.readAllBytes(file.toPath());

try (InputStream in = new FileInputStream(file);OutputStream out = new BufferedOutputStream(response.getOuptputStream())) {  // 每次读1KB  byte[] buffer = new byte[1024];  int len;  while ((len = in.read(buffer)) != -1) {    out.write(buffer, 0 ,len);  }  out.flush(); } catch (IOExcepetion e) {   throw new RuntimeException("下载失败", e); }

try (FileInputStream fis = new FileInputStream(file);    FileChannel fileChannel = fis.getChannel()) {    long position = 0;    long size = fileChannel.size();    WritableByteChannel writableChannel = Channels.newChannel(response.getOutputStream());    // 每次传输最多8KB的倍数, 但 transferTo 会尽量利用 DMA一次传更多    while (position < size) {      long transfered = fileChannel.transferTo(position, sizd - position, writableChannel);      if (transfered <= 0) break;      position += transfered;     }}

long fileLength = file.length();Sting fileName = URLEncoder.encode(file.getName(), StandardCharsets.UTF_8);String rangeHeader = request.getHeader("Range");long start = 0;long end = fileLength - 1;//解析 Range 头if (rangeHeader != null && rangeHeader.startsWith("bytes=")) {  String rangeValue = rangeHeader.substring("bytes=".length());  String[] parts = rangeValue.split("-");  try {    start = Long.parseLong(parts[0]);    if (parts.length > 1 && !parts[1].isEmpty()) {      end = Long.parseLong(parts[1]);        }   } catch (NumberFormatException e) {       response.sendError(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);       return;   }    if (start < 0 || start > end || end >= fileLength) {     response.setStatus(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);     return;   }}