Question

我可以将图像作为byte []获取，并使用form.jsp和FormFile将其存储在我的数据库中。现在我需要能够检索该byte []并将其作为图像显示在JSP中。有没有办法创建资源并检索该图像？

Answer 1

public ActionForward pageLoad(ActionMapping a,ActionForm b,HttpServletRequest c,HttpServletResponse d){
    b.setImageData(loadImageData());
    return a.findForward("toPage");
}

public ActionForward imageLoad(ActionMapping a,ActionForm b,HttpServletRequest c,HttpServletResponse d){
    byte[] tempByte = b.getImageData();
    d.setContentType("image/jpeg");
    ServletOutputStream stream = d.getOutputStream();
    /*
        Code to write tempByte into stream here.
    */
    return null;
}

将tempByte写入stream，刷新并关闭它。 return null来自行动。

现在从<img src="yourAction.do">

中调用操作

Answer 2

       <%@ page import="java.sql.*" %>
       <%@ page import="java.io.*" %> 

        Connection connection =  null;

      String connectionURL = "jdbc:mysql://localhost:3306/Test";
      ResultSet rs = null;

       PreparedStatement psmnt = null;

 InputStream sImage;
 try {

Class.forName("com.mysql.jdbc.Driver").newInstance();

 connection = DriverManager.getConnection(connectionURL, "Admin", "Admin");
psmnt = connection.prepareStatement("SELECT image FROM save_image WHERE id = ?");
psmnt.setString(1, "11"); // here integer number '11' is image id from the table
rs = psmnt.executeQuery();
if(rs.next()) {
byte[] bytearray = new byte[1048576];
int size=0;
sImage = rs.getBinaryStream(1);
response.reset();
response.setContentType("image/jpeg");
while((size=sImage.read(bytearray))!= -1 ){
response.getOutputStream().write(bytearray,0,size);
 }
 }
 }
     catch(Exception ex){
           out.println("error :"+ex);
        }
            finally {
                  rs.close();
                 psmnt.close();
                 connection.close();
         }
                  %>

通过这个你可以从数据库中检索图像

使用struts从字节数组中显示jsp中的图像

2 个答案: