Servlet 视频流，但视频不显示，音频正在工作

Question

所以我目前正在编写一个 java ee 后端，我可以在其中存储图片或视频，并且我想在 html5

import com.dispway.restserver.facade.PlaylistEntryFacade;
import com.dispway.restserver.smallModel.SmallPlaylistEntry;

import javax.ejb.EJB;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.IOException;


@WebServlet("entry")
public class PlaylistEntryServlet extends HttpServlet {
    @EJB
    PlaylistEntryFacade playlistEntryFacade;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        //entry-id
        String e_id = req.getParameter("e_id");
        //entry-type
        String type = req.getParameter("type");
        SmallPlaylistEntry entry = playlistEntryFacade.findById(Integer.parseInt(e_id));
        ServletContext context = getServletContext();
        String mimeType;
        ServletOutputStream outputStream;

        switch (type) {
            case "1":
                System.out.println("image-type");
                mimeType = context.getMimeType(entry.getFilename());
                if (mimeType == null) {
                    mimeType = "image/png";
                }
                resp.setContentType(mimeType);
                outputStream = resp.getOutputStream();
                outputStream.write(entry.getFile());
                outputStream.close();

                break;
            case "2":
                // NOT WORKING, I only get BlackScreen

                System.out.println("video-type");
                System.out.println(entry.getFilename());
                mimeType = context.getMimeType(entry.getFilename());
                if (mimeType == null) {
                    System.out.println("mime is null");
                    mimeType = "video/mp4";
                }
                System.out.println("MimeType: " + mimeType);
                resp.setContentType(mimeType);
                resp.setContentLength(entry.getFile().length);
                //getFile returns a byte[]
                BufferedInputStream bufferedInputStream = new BufferedInputStream(new ByteArrayInputStream(entry.getFile()));
                byte[] content = new byte[4096];
                int bytesRead;
                outputStream = resp.getOutputStream();
                while ((bytesRead = bufferedInputStream.read(content)) != -1) {
                    outputStream.write(content, 0, bytesRead);
                }
                bufferedInputStream.close();
                outputStream.close();
                break;
        }

    }
}

Answer 1

抱歉，视频编解码器错误，因此 html <video> 没有显示视频。