视频文件保存在不为人知的地方，总之前端不能直接访问的位置，需要通过后端接口取出来再返回给前端。前端这样子播放
src=后端接口如果后端直接这样子写
//path为本地文件路劲
public void play(String path, HttpServletRequest request, HttpServletResponse response) {
//获取视频文件流
FileInputStream fileInputStream = null;
OutputStream outputStream = null;
try {
outputStream = response.getOutputStream();
fileInputStream = new FileInputStream(new File(path));
byte[] cache = new byte[1024];
response.setHeader(HttpHeaders.CONTENT_TYPE, 'video/mp4');
response.setHeader(HttpHeaders.CONTENT_LENGTH, fileInputStream.available()+'');
int flag;
while ((flag = fileInputStream.read(cache)) != -1) {
outputStream.write(cache, 0, flag);
}
outputStream.flush();
outputStream.close();
}catch (Exception e){
log.error('文件传输错误', e);
throw new RuntimeException('文件传输错误');
} finally{
if(outputStream != null){
try {
outputStream.close();
} catch (IOException e) {
log.error('流释放错误', e);
}
}
if(fileInputStream != null){
try {
fileInputStream.close();
} catch (IOException e) {
log.error('文件流释放错误', e);
}
}
}
}
小视频问题不大，视频大的话会因为卡顿很久，查看请求发现会先请求整个视频一次才开始播放，以此获取视频大小等信息。所以后端接口需要支持分段下载，这样才能边播放边下载
//path为本地文件路劲
public void play(String path, HttpServletRequest request, HttpServletResponse response) {
RandomAccessFile targetFile = null;
OutputStream outputStream = null;
try {
outputStream = response.getOutputStream();
response.reset();
//获取请求头中Range的值
String rangeString = request.getHeader('Range');
//打开文件
File file = new File(path);
if (file.exists()) {
//使用RandomAccessFile读取文件
targetFile = new RandomAccessFile(file, 'r');
long fileLength = targetFile.length();
long requestSize = (int) fileLength;
//分段下载视频
if (StringUtils.hasText(rangeString)) {
//从Range中提取需要获取数据的开始和结束位置
long requestStart = 0, requestEnd = 0;
String[] ranges = rangeString.split('=');
if (ranges.length > 1) {
String[] rangeDatas = ranges[1].split('-');
requestStart = Integer.parseInt(rangeDatas[0]);
if (rangeDatas.length > 1) {
requestEnd = Integer.parseInt(rangeDatas[1]);
}
}
if (requestEnd != 0 && requestEnd > requestStart) {
requestSize = requestEnd - requestStart + 1;
}
//根据协议设置请求头
response.setHeader(HttpHeaders.ACCEPT_RANGES, 'bytes');
response.setHeader(HttpHeaders.CONTENT_TYPE, 'video/mp4');
if (!StringUtils.hasText(rangeString)) {
response.setHeader(HttpHeaders.CONTENT_LENGTH, fileLength + '');
} else {
long length;
if (requestEnd > 0) {
length = requestEnd - requestStart + 1;
response.setHeader(HttpHeaders.CONTENT_LENGTH, '' + length);
response.setHeader(HttpHeaders.CONTENT_RANGE, 'bytes ' + requestStart + '-' + requestEnd + '/' + fileLength);
} else {
length = fileLength - requestStart;
response.setHeader(HttpHeaders.CONTENT_LENGTH, '' + length);
response.setHeader(HttpHeaders.CONTENT_RANGE, 'bytes ' + requestStart + '-' + (fileLength - 1) + '/'
+ fileLength);
}
}
//文段下载视频返回206
response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT);
//设置targetFile，从自定义位置开始读取数据
targetFile.seek(requestStart);
} else {
//如果Range为空则下载整个视频
response.setHeader(HttpHeaders.CONTENT_DISPOSITION, 'attachment; filename=test.mp4');
//设置文件长度
response.setHeader(HttpHeaders.CONTENT_LENGTH, String.valueOf(fileLength));
}
//从磁盘读取数据流返回
byte[] cache = new byte[4096];
try {
while (requestSize > 0) {
int len = targetFile.read(cache);
if (requestSize < cache.length) {
outputStream.write(cache, 0, (int) requestSize);
} else {
outputStream.write(cache, 0, len);
if (len < cache.length) {
break;
}
}
requestSize -= cache.length;
}
} catch (IOException e) {
// tomcat原话。写操作IO异常几乎总是由于客户端主动关闭连接导致，所以直接吃掉异常打日志
//比如使用video播放视频时经常会发送Range为0- 的范围只是为了获取视频大小，之后就中断连接了
log.info(e.getMessage());
}
} else {
throw new RuntimeException('文件路劲有误');
}
outputStream.flush();
} catch (Exception e) {
log.error('文件传输错误', e);
throw new RuntimeException('文件传输错误');
}finally {
if(outputStream != null){
try {
outputStream.close();
} catch (IOException e) {
log.error('流释放错误', e);
}
}
if(targetFile != null){
try {
targetFile.close();
} catch (IOException e) {
log.error('文件流释放错误', e);
}
}
}
}
文章为作者独立观点，不代表股票交易接口观点
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