Merge remote-tracking branch 'origin/master'

src/com/hellogithub/servlet/DeleteCookie.java

@@ -0,0 +1,58 @@
+package com.hellogithub.servlet;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.Cookie;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+
+@WebServlet("/deletecookie")
+public class DeleteCookie extends HttpServlet {
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        doPost(req,resp);
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        /*
+*/
+// 获取cookie数组
+        Cookie[] cookies = req.getCookies();
+// 判断数组对象是否为null
+        if (cookies != null) {
+            // 遍历cookie数组
+            for(Cookie cookie : cookies) {
+                // 获取cookie的name属性值
+                String cName = req.getParameter("username");
+                // 通过name属性值,获取要删除的特定cookie
+                if ("username".equals(cName)) {
+                    // 找到了要删除的特定cookie,cName为要删除特定cookie的name属性值
+            /*
+              新建一个cookie对象
+               其name属性值和要删除的特定的cookie的name属性值完全相同
+               其value属性值可以为任意值或null
+            */
+                    Cookie nc = new Cookie(cName,null);
+
+//               设置新建cookie的有效时间,由于要删除特定的cookie所以设置为0
+
+                    nc.setMaxAge(0);
+            /*
+               设置新建cookie的path
+               注意:新建cookie的path和要删除的特定cookie的path一定要相同
+              否则无法删除
+            */
+                    nc.setPath(req.getContextPath());
+            /*
+               将新建的cookie响应给浏览器即删除特定的cookie
+            */
+                    resp.addCookie(nc);
+                }
+            }
+        }
+    }
+}