应用场景:用于自动登录, 浏览记录, 购物车等等。
使用Cookie步骤如下:
-
首先添加Cookie
resp.addCookie(new Cookie("name", "张三"));
-
获取Cookie
Cookie[] cookies = req.getCookies();
-
获取Cookie的name以及value
String name = cookie.getName();
String value = cookie.getValue();
完整代码如下:
public class CookieServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setCharacterEncoding("utf-8");
resp.setContentType("text/html;charset=utf-8");
PrintWriter out = resp.getWriter();
小案例:获取上一次的访问时间。
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setCharacterEncoding("utf-8");
resp.setContentType("text/html;charset=utf-8");
PrintWriter out = resp.getWriter();
Cookie[] cookies = req.getCookies();
if(cookies != null) {