我正在尝试通过struts2 Java框架从数据库博客数据类型中检索JSP中的图像，但显示空白

我的JSP页面

   <tbody>
       <% int n=1; %>
          <s:iterator value="dataList">
              <tr>
                  <th><% out.print(n); %></th>
                  <th>
                     <s:property value="postTitle" />
                   </th>
                   <th>
                      <s:property value="postDescription"/>
                   </th>
                   <th>
                      <img width="100" height="auto" src="<s:url value="Post?url=" /><s:property value="postUrl" />" />
                   </th>
               </tr>
               <% n=n+1; %>
           </s:iterator>
    </tbody>

和Pujo Page

String postTitle;
String postUrl;
String postDescription;
File postImage;

 // Getter Setter

Dao文件为：

public ResultSet getPost() {
    try {
        Connection conn = Connectionmanager.getconnection();
        return conn.prepareStatement("SELECT posttitle,posturl,postbody,postmetadescription,postauthor,categery FROM blogpost ORDER BY id DESC").executeQuery();
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    }
}

public ResultSet getPostimage(String url) {
    try {
        Connection conn = Connectionmanager.getconnection();
        PreparedStatement ps = conn.prepareStatement("SELECT postimage FROM blogpost WHERE posturl=?");
        ps.setString(1,url);
        return ps.executeQuery();
    } catch (ClassnotFoundException | SQLException e) {
        e.printStackTrace();
        return null;
    }
}

动作文件代码

  public String execute() throws Exception {
    HttpServletResponse response = ServletactionContext.getResponse();
    HttpServletRequest request = ServletactionContext.getRequest();
    String url = request.getParameter("url");
    try {
        dataList = new ArrayList<>();
        rs = new PostDao().getPost();
        if (rs != null) {
            while (rs.next()) {
                dataBean = new PostInfo();
                dataBean.setPostTitle(rs.getString("posttitle"));
                dataBean.setPostUrl(rs.getString("posturl"));
                dataBean.setPostBody(rs.getString("postbody"));
                dataBean.setPostDescription(rs.getString("postmetadescription"));
                dataBean.setPostAuthor(rs.getString("postauthor"));
                dataBean.setPostCategery(rs.getString("categery"));
                dataList.add(dataBean);
            }
        }
        try {
            rs = new PostDao().getPostimage(url);
            if (rs.next()) {
                Blob ph = rs.getBlob("postimage");
                byte[] data = ph.getBytes(1,(int) ph.length());
                response.setHeader("expires","0");
                response.setContentType("image/jpg");
                OutputStream out = response.getOutputStream();
                out.write(data);
                out.flush();
                out.close();

            }

        } catch (IOException | SQLException e) {
            e.printStackTrace();
            e.getMessage();
        }

    } catch (Exception e) {
        e.printStackTrace();
    }
    return SUCCESS;
}