----------文件上传
- 文件上传是使用ajax一个工具来接受request得到的数据,其中上传到requset需要注意type,name,和上传方式enctype,形成文件块,之后使用特殊接口将文件快加以识别取出相应的上传文件部分,其中可以设置缓存大小,缓存位置,存储位置和存完即删除缓存等设置。
- 上传接受(需注意中文问题)上传可设置缓存大小,和缓存位置
----------html上传时候会分文件块自动,但接受需要手动(接受并写入服务器)
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
//接受上传文件
//1、创建磁盘文件项工厂
DiskFileItemFactory factory = new DiskFileItemFactory();
//2、创建文件上传的核心类
ServletFileUpload upload = new ServletFileUpload(factory);
//3、解析request---获得文件项集合
List<FileItem> parseRequest = upload.parseRequest(request);
//4、遍历文件项集合
for(FileItem item : parseRequest){
//5、判断普通表单项/文件上传项
boolean formField = item.isFormField();//是否是一个普通表单项
if(formField){
//普通表单项
String fieldName = item.getFieldName();
String fieldValue = item.getString();
System.out.println(fieldName+":"+fieldValue);
}else{
//文件上传项
//获得上传文件的名称
String fileName = item.getName();
//获得上传文件的内容
InputStream in = item.getInputStream();
//将in中的数据拷贝服务器上
String path = this.getServletContext().getRealPath("upload");
OutputStream out = new FileOutputStream(path+"/"+fileName);
int len = 0;
byte[] buffer = new byte[1024];
while((len=in.read(buffer))>0){
out.write(buffer, 0, len);
}
in.close();
out.close();
}
}
} catch (FileUploadException e) {
e.printStackTrace();
}
}
----------------------api运用
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
//1、创建磁盘文件项工厂
//作用:设置缓存文件的大小 设置临时文件存储的位置
String path_temp = this.getServletContext().getRealPath("temp");
//DiskFileItemFactory factory = new DiskFileItemFactory(1024*1024, new File(path_temp));
DiskFileItemFactory factory = new DiskFileItemFactory();
factory.setSizeThreshold(1024*1024);
factory.setRepository(new File(path_temp));
//2、创建文件上传的核心类
ServletFileUpload upload = new ServletFileUpload(factory);
//设置上传文件的名称的编码
upload.setHeaderEncoding("UTF-8");
//ServletFileUpload的API
boolean multipartContent = upload.isMultipartContent(request);//判断表单是否是文件上传的表单
if(multipartContent){
//是文件上传的表单
//***解析request获得文件项集合
List<FileItem> parseRequest = upload.parseRequest(request);
if(parseRequest!=null){
for(FileItem item : parseRequest){
//判断是不是一个普通表单项
boolean formField = item.isFormField();
if(formField){
//username=zhangsan
String fieldName = item.getFieldName();
String fieldValue = item.getString("UTF-8");//对普通表单项的内容进行编码
System.out.println(fieldName+"----"+fieldValue);
//当表单是enctype="multipart/form-data"时 request.getParameter相关的方法
//String parameter = request.getParameter("username");
}else{
//文件上传项
//文件的名
String fileName = item.getName();
//获得上传文件的内容
InputStream in = item.getInputStream();
String path_store = this.getServletContext().getRealPath("upload");
OutputStream out = new FileOutputStream(path_store+"/"+fileName);
IOUtils.copy(in, out);
in.close();
out.close();
//删除临时文件
item.delete(); }
} }
}else{
//不是文件上传表单
//使用原始的表单数据的获得方式 request.getParameter();
}
} catch (FileUploadException e) {
e.printStackTrace();
}}
- 环境分tom服务器和本地
- 使用阿帕奇的工具fileupload来接受上传的内容
- 必须是post提交,type必须file,必须有name;"multipart/form-data多部分表单
<body>
<form action="/WEB32/fileuploadServlet2" method="post" enctype="multipart/form-data">
<input type="text" name="username"><br>
<input type="file" name="filename"><br>
<input type="submit" value="上传文件">
</form>
</body>
---------用户注销要记得把自动登录的cookie同样删掉
//用户注销
public void logout(HttpServletRequest request, HttpServletResponse response) throws IOException{
HttpSession session = request.getSession();
//从session中将user删除
session.removeAttribute("user");
//将存储在客户端的cookie删除掉
Cookie cookie_username = new Cookie("cookie_username","");
cookie_username.setMaxAge(0);
//创建存储密码的cookie
Cookie cookie_password = new Cookie("cookie_password","");
cookie_password.setMaxAge(0);
response.addCookie(cookie_username);
response.addCookie(cookie_password);
response.sendRedirect(request.getContextPath()+"/login.jsp"); }
------------------提取代码权限控制
- filter过滤,使用注意转成http,xml配置要配置在自动登录后面(主要看mapping顺序)否则自动登录失效
---------xml--将需要过滤的都写在同一个虚拟目录下
<!-- 用防护登录权限配置在自动登录的后面 -->
<!-- <filter>
<filter-name>UserLoginPrivilegeFilter</filter-name>
<filter-class>com.itheima.web.filter.UserLoginPrivilegeFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>UserLoginPrivilegeFilter</filter-name>
<url-pattern>/privilege/*</url-pattern>
</filter-mapping> -->
-------filter
public class UserLoginPrivilegeFilter implements Filter {
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse resp = (HttpServletResponse) response;
// 校验用户是否登录----校验session是否存在user对象
HttpSession session = req.getSession();
// 判断用户是否已经登录 未登录下面代码不执行
User user = (User) session.getAttribute("user");
if (user == null) {
// 没有登录
resp.sendRedirect(req.getContextPath() + "/login.jsp");
return;
}
chain.doFilter(req, resp); }
--------------我的订单集合
- 使用maplisthandler把多表查询没有实体对应结果封装
- 封装实体,一对一连表查,一对多分开sql而后搭配for循环
- 可以通过一条sql查出三张表信息,但是会有信息重复
-------两表联查(一对一)
public List<Map<String, Object>> findAllOrderItemByOid(String oid) throws SQLException {
QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());
String sql = "select i.count,i.subtotal,p.pimage,p.pname,p.shop_price from orderitem i,product p where i.pid=p.pid and i.oid=?";
List<Map<String, Object>> mapList = runner.query(sql, new MapListHandler(), oid);
return mapList;
}
------------------servlet
// 获得我的订单
public void myOrders(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
HttpSession session = request.getSession();
User user = (User) session.getAttribute("user");
ProductService service = new ProductService();
// 查询该用户的所有的订单信息(单表查询orders表)
// 集合中的每一个Order对象的数据是不完整的 缺少List<OrderItem> orderItems数据
List<Order> orderList = service.findAllOrders(user.getUid());
// 循环所有的订单 为每个订单填充订单项集合信息
if (orderList != null) {
for (Order order : orderList) {
// 获得每一个订单的oid
String oid = order.getOid();
// 查询该订单的所有的订单项---mapList封装的是多个订单项和该订单项中的商品的信息
List<Map<String, Object>> mapList = service.findAllOrderItemByOid(oid);
// 将mapList转换成List<OrderItem> orderItems
for (Map<String, Object> map : mapList) {
try {
// 从map中取出count subtotal 封装到OrderItem中
OrderItem item = new OrderItem();
// item.setCount(Integer.parseInt(map.get("count").toString()));
BeanUtils.populate(item, map);
// 从map中取出pimage pname shop_price 封装到Product中
Product product = new Product();
BeanUtils.populate(product, map);
// 将product封装到OrderItem
item.setProduct(product);
// 将orderitem封装到order中的orderItemList中
order.getOrderItems().add(item);
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
} } } }
// orderList封装完整了
request.setAttribute("orderList", orderList);
request.getRequestDispatcher("/order_list.jsp").forward(request, response);
}
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