public void showPicture(){ 
    String id = ServletActionContext.getRequest().getParameter("id");//前台传来的存图片路径实体类的主键id 
    HttpServletResponse response = ServletActionContext.getResponse();//struts2获取response 
    if(id != null && !"".equals(id)){ 
      this.classicCases = this.classicCasesManager.findClassicCasesById(id); 
      String pic_path = this.classicCases.getImagesLocalPath();//图片路径 
      FileInputStream is; 
      try { 
        is = new FileInputStream(pic_path); 
        int i = is.available(); // 得到文件大小 
        byte data[] = new byte[i]; 
        is.read(data); // 读数据 
        is.close(); 
        response.setContentType("image/*"); // 设置返回的文件类型 
        OutputStream toClient = response.getOutputStream(); // 得到向客户端输出二进制数据的对象 
        toClient.write(data); // 输出数据 
        toClient.close(); 
      } catch (FileNotFoundException e) { 
        e.printStackTrace(); 
      } catch (IOException e) { 
        e.printStackTrace(); 
      } 
    } 
  } 

<img alt=""  src="<%=basePath %>ClassicCasesAction!showPicture.action?id=${classicCases.id}">