java之cookie

 

package test;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Set;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Cookie的操作类
 * @author shy.qiu
 *
 */
public class CookieHandler {
    /**
     * 创建cookie
     *
     * @param response
     *            回应
     * @param nameValues
     *            存入cookie的键值对
     * @param days
     *            设置cookie的有效期
     */
    public static void createCookie(HttpServletResponse response,
            Hashtable<String, String> nameValues, int days) {
        Set<String> set = nameValues.keySet();
        Iterator<String> it = set.iterator();
        for (; it.hasNext();) {
            String name = (String) it.next();
            String value = (String) nameValues.get(name);
            // 生成新的cookie
            Cookie cookie = new Cookie(name, value);
            // 设置有效日期
            cookie.setMaxAge(days * 24 * 60 * 60);
            // 设置路径（默认）
            cookie.setPath("/");
            // 把cookie放入响应中
            response.addCookie(cookie);
        }
    }
    /**
     * 读取Cookie
     *
     * @param request
     * @return Hashtable 返回cookie的键值对
     */
    public static Hashtable<String, String> getCookies(
            HttpServletRequest request) {
        Cookie[] cookies = request.getCookies();
        Hashtable<String, String> cookieHt = new Hashtable<String, String>();
        if (cookies.length > 0) {
            for (int i = 0; i < cookies.length; i++) {
                Cookie cookie = cookies[i];
                cookieHt.put(cookie.getName(), cookie.getValue());
            }
        }
        return cookieHt;
    }
    /**
     * 修改cookie中指定键的值
     *
     * @param request
     * @param name
     *            指定的键
     * @param value
     *            值
     */
    public static void setCookieValueByName(HttpServletRequest request,
            String name, String value) {
        Cookie[] cookies = request.getCookies();
        if (cookies.length > 0) {
            for (int i = 0; i > cookies.length; i++) {
                if (name.equalsIgnoreCase(cookies[i].getName())) {
                    cookies[i].setValue(value);
                }
            }
        }
    }
    /**
     * 得到指定键的值
     *
     * @param request
     * @param name
     *            指定的键
     * @return String 值
     */
    public static String getCookieValueByName(HttpServletRequest request,
            String name) {
        Cookie[] cookies = request.getCookies();
        String resValue = "";
        if (cookies.length > 0) {
            for (int i = 0; i > cookies.length; i++) {
                if (name.equalsIgnoreCase(cookies[i].getName())) {
                    resValue = cookies[i].getValue();
                }
            }
        }
        return resValue;
    }
    /**
     * 销毁cookie
     *
     * @param request
     * @param response
     */
    public static void deletesCookie(HttpServletRequest request,
            HttpServletResponse response) {
        Cookie[] cookies = request.getCookies();
        if (cookies != null) {
            for (int i = 0; i < cookies.length; i++) {
                Cookie cookie = cookies[i];
                // 销毁
                cookie.setMaxAge(0);
                response.addCookie(cookie);
            }
        }
    }
}