JSP实现图片上传并保存到数据库

servlet里面有一个request.getPart()方法，通过这个文件可以获得图片，前提是你的servlet版本必须是3.0以上+tomcat7，具体参考以下
@WebServlet("/articleManage")
@MultipartConfig(maxFileSize = 1024 * 1024 * 10)
// 最大10MB
public class ArticleManage extends HttpServlet {
private static final long serialVersionUID = 1L;

public ArticleManage() {
super();
}

protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
doPost(request, response);

}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String method = request.getParameter("method");
if (method != null) {

if (method.equals("add")) {
addArticle(request, response);
}
}
private void addArticle(HttpServletRequest request,
HttpServletResponse response) {
ArticleService service = new ArticleServiceImpl();
ArticleTypeService typeService=new ArticleTypeServiceImpl();
String content = null;
String email = null;
String tag = null;
String type=null;
try {
email = request.getParameter("email");
content = request.getParameter("content");
tag = request.getParameter("tag");
type=request.getParameter("type");
Part img = request.getPart("img");
String imgName = null;
if (img != null) {
// 设置文件路径，写到硬盘

String head = img.getHeader("content-disposition");
int index = head.lastIndexOf("=") + 2;
imgName = head.substring(index, head.length() - 1); // 上传文件时的文件名
imgName.lastIndexOf(".");
String suffix = imgName.substring(imgName.lastIndexOf(".")); // 文件后缀

if (!suffix.equals(".jpeg") && !suffix.equals(".jpg")
&& !suffix.equals(".png") && !suffix.equals(".gif")
&& !suffix.equals(".bmp")) {
System.out.println("innn******************");
// 非法文件

request.setAttribute("content", content);
request.setAttribute("email", email);
request.setAttribute("tag", tag);
request.setAttribute("type", type);
request.setAttribute("errorinfo",
"*您上传的文件不合法，只能上后缀为jpg,bmp,png,gif,jpeg的图片");
request.getRequestDispatcher("add.jsp").forward(request,
response); // 重新导航到表单页
return;
}

imgName = System.currentTimeMillis() + suffix;
img.write(this.getServletContext().getRealPath("/image/upload")
+ File.separator + imgName); // 写到硬盘
}
Article msg = new Article();
msg.setContent(content);
msg.setImg("image/upload/" + imgName);
msg.setEmail(email);
msg.setKeyWord(tag);
msg.setType(typeService.querySingle(Integer.parseInt(type)));
// 从session中取User
User user = (User) request.getSession().getAttribute("user");
msg.setUser(user);
service.addMsg(msg);
response.setCharacterEncoding("utf-8");
response.setContentType("text/html");
response.getWriter()
.write("