Java实现http请求文件流对带宽限速获取md5值

 
public static String getMd5(String url, String type) {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        final long MAX_BPS = 2 * 1024 * 1024; // 200Mbps = 25MB/s
        MessageDigest md;
        // 创建时间格式化器（线程安全）
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSS");
        try {
            md = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("MD5 algorithm not found", e);
        }
        try (CloseableHttpResponse response = httpClient.execute(new HttpGet(url))) {
            HttpEntity entity = response.getEntity();
            if (entity == null) {
                return "";
            }
            // 记录开始时间
            long startTime = System.currentTimeMillis();
            try (InputStream in = entity.getContent()) {
                byte[] buffer = new byte[8192];
                int bytesRead;
                long totalBytes = 0;
                while ((bytesRead = in.read(buffer)) != -1) {
                    md.update(buffer, 0, bytesRead);
                    totalBytes += bytesRead;
                    // 动态限速逻辑
                    long elapsed = System.currentTimeMillis() - startTime;
                    long expectedTime = (totalBytes * 1000) / MAX_BPS;
                    if (elapsed < expectedTime) {
                        Thread.sleep(expectedTime - elapsed);
                    }
                }
                // 计算最终统计信息
                long endTime = System.currentTimeMillis();
                double timeCost = DoubleUtils.formatDouble((endTime - startTime) / 1000.0);
                String sizeMB = String.format("%.3f", DoubleUtils.formatDouble(totalBytes / (1024.0 * 1024)));
                // 生成MD5
                String md5 = DatatypeConverter.printHexBinary(md.digest()).toLowerCase();
                // 完整日志输出
                log.info("下载完成 | 类型: {} | MD5: {} | 大小: {}MB | 耗时: {}s",
                        type, md5, sizeMB, timeCost);
                return md5;
            }
        } catch (Exception e) {
            // 记录异常发生时间
            String errorTime = LocalDateTime.now().format(formatter);
            log.error("下载失败 | 类型: {} | 错误时间: {} | 原因: {}",
                    type, errorTime, e.getMessage());
            return "";
        }finally {
            try {
                httpClient.close();
            }catch (Exception e) {
            }
        }
    }