常用cookie處理方法工具類，cookie工具類

常用cookie處理方法工具類，cookie工具類

功能：cookie的添加、刪除、獲取值

 1 import java.io.UnsupportedEncodingException;
 2 import java.net.URLDecoder;
 3 
 4 import javax.servlet.http.Cookie;
 5 import javax.servlet.http.HttpServletRequest;
 6 import javax.servlet.http.HttpServletResponse;
 7 
 8 /**
 9  * 常用cookie處理方法工具類
10  */
11 public class CookieUtil {
12     
13     /**
14      * 添加cookie
15      * @param response
16      * @param key cookie主鍵
17      * @param value cookie值
18      */
19     public static void addCookie(HttpServletResponse response, String key, String value){
20         Cookie cookie = new Cookie(key, value);
21         cookie.setPath("/");// 這個要設置  
22         cookie.setMaxAge(60*60*24*30);//保留一個月 以秒為單位  
23         response.addCookie(cookie);
24     }
25     
26     /**
27      * 刪除cookie
28      * @param request
29      * @param response
30      * @param key cookie主鍵
31      */
32     public static void deleteCookie(HttpServletRequest request, HttpServletResponse response, String key){
33         Cookie cookies[] = request.getCookies();  
34         if (cookies != null) {  
35             for (int i = 0; i < cookies.length; i++) {  
36                 if (cookies[i].getName().equals(key)) {  
37                     Cookie cookie = new Cookie(key,null);
38                     cookie.setPath("/");//設置成跟寫入cookies一樣的  
39                     cookie.setMaxAge(0);  
40                     response.addCookie(cookie);  
41                 }  
42             }  
43         }  
44     }
45     
46     /**
47      * 取得cookie的值
48      * @param request
49      * @param key cookie主鍵
50      */
51     public static String getCookieValue(HttpServletRequest request, String key) throws UnsupportedEncodingException{
52         for(Cookie cookie : request.getCookies()){
53             if (cookie.getName().equals(key)) {   
54                 return URLDecoder.decode(cookie.getValue(), "UTF-8");  
55             }  
56         }
57         return null;
58     }
59 }