cookie工具类

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


public class CookieHelper {
    
    
    /**
     * 设置cookie有效期，根据需要自定义[本系统设置为30天]
     */
    private final static int COOKIE_MAX_AGE = 60 * 60 * 24 * 30;

    /**
     * 
     * @desc 删除指定Cookie
     * @param response
     * @param cookieName
     *            cookie的名称
     */
    public static void removeCookie( HttpServletRequest request, HttpServletResponse response,
            String cookieName) {

        Cookie[] cookies = request.getCookies();
        for (int i = 0; i < cookies.length; i++) {
            Cookie cookie = new Cookie(cookieName, null);
            cookie.setMaxAge(0);
            response.addCookie(cookie);
        }
    }

    /**
     * 
     * @desc 删除指定Cookie
     * @param response
     * @param cookie
     * @param domain
     */
    public static void removeCookie(HttpServletRequest request , HttpServletResponse response,
            String cookieName, String domain) {
        Cookie[] cookies = request.getCookies();
        for (int i = 0; i < cookies.length; i++) {
            Cookie cookie = new Cookie(cookieName, null);
            cookie.setMaxAge(0);
            cookie.setDomain(domain);
            response.addCookie(cookie);
        }
    }

    /**
     * 
     * @desc 根据Cookie名称得到Cookie的值，没有返回Null
     * @param name
     *            Cookie名称
     * @return
     */
    public static String getCookieValue(HttpServletRequest request ,String name) {

        Cookie cookie = getCookie(request , name);
        if (cookie != null) {
            return cookie.getValue();
        } else {
            return null;
        }
    }

    /**
     * 
     * @desc 根据Cookie名称得到Cookie对象，不存在该对象则返回Null
     * @param request
     * @param name
     */
    public static Cookie getCookie(HttpServletRequest request , String name) {

        Cookie cookies[] = request.getCookies();
        if (cookies == null || name == null || name.length() == 0) {
            return null;
        }
        Cookie cookie = null;
        for (int i = 0; i < cookies.length; i++) {
            if (!cookies[i].getName().equals(name)) {
                continue;
            }
            cookie = cookies[i];
            if (request.getServerName().equals(cookie.getDomain())) {
                break;
            }
        }
        return cookie;
    }

    /**
     * 
     * @desc 添加一条新的Cookie信息，默认有效时间为一个月
     * @param response
     * @param name
     * @param value
     */
    public static void setCookie(HttpServletResponse response, String name,
            String value) {
        setCookie(response, name, value, COOKIE_MAX_AGE);
    }

    /**
     * 
     * @desc 添加一条新的Cookie信息，可以设置其最长有效时间(单位：秒)
     * @param response
     * @param name
     * @param value
     * @param maxAge
     */
    public static void setCookie(HttpServletResponse response, String name,
            String value, int maxAge) {
        if (value == null) {
            value = "";
        }
        Cookie cookie = new Cookie(name, value);
        if (maxAge > 0) {
            cookie.setMaxAge(maxAge);
        } else {
            cookie.setMaxAge(COOKIE_MAX_AGE);
        }
        response.addCookie(cookie);
    }

}