泛型编程实例之（二）
基本泛型类：
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public abstract class SessionServiceBase<T> {public abstract String getStringFromEntry(T entry); /** * 存储介质的存储string，比如cookie里、threadlocal里等 * * @param value * @param seconds */public abstract void setString(String value, int seconds);public void set(T entry) {// 写入cookieset(entry, 3600 * 24 * 30); // 默认30天}public final void set(T entry, int seconds) {String value = getStringFromEntryInternal(entry);setString(value, seconds);}String getStringFromEntryInternal(T entry) {String s = getStringFromEntry(entry);return StringUtil.signContent(s, getSalt());}}?抽象泛型类的实现类：
public class CookieSessionService extends SessionServiceBase<User> {private tools.web.CookieUtil cookie = null;。。。@Overridepublic void setString(String arg0, int arg1) {try {cookie.set(name, URLEncoder.encode(arg0, ENCODING), domain, null,arg1);} catch (UnsupportedEncodingException e) {}}}?
调用它的类：
public class Request extends HttpServlet {protected void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {long startTime = System.currentTimeMillis();request.setCharacterEncoding("GBK");String action = request.getParameter("action"); ....if ("auth".equalsIgnoreCase(action)) {auth(request, response);return; ....private void auth(HttpServletRequest request, HttpServletResponse response) {String name = request.getParameter("name");CookieSessionService cs = CookieSessionService.create(request,response, "auth", null);User u = new User();u.setUserId(0);u.setUserName(name);u.setData(request.getParameter("data"));cs.set(u);}}??
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