持久化cookie之前，我们最好了解一下cookie是怎么传输的，看完之后我想你就能使用很简单的方式去保持cookie了。

/** * This interceptor put all the Cookies in Preferences in the Request. * Your implementation on how to get the Preferences MAY VARY. * <p> * Created by tsuharesu on 4/1/15. */public class AddCookiesInterceptor implements Interceptor {    @Override    public Response intercept(Chain chain) throws IOException {        Request.Builder builder = chain.request().newBuilder();        HashSet<String> preferences = (HashSet) Preferences.getDefaultPreferences().getStringSet(Preferences.PREF_COOKIES, new HashSet<>());        for (String cookie : preferences) {            builder.addHeader("Cookie", cookie);            Log.v("OkHttp", "Adding Header: " + cookie); // This is done so I know which headers are being added; this interceptor is used after the normal logging of OkHttp        }        return chain.proceed(builder.build());    }}

/** * This Interceptor add all received Cookies to the app DefaultPreferences. * Your implementation on how to save the Cookies on the Preferences MAY VARY. * <p> * Created by tsuharesu on 4/1/15. */public class ReceivedCookiesInterceptor implements Interceptor {    @Override    public Response intercept(Chain chain) throws IOException {        Response originalResponse = chain.proceed(chain.request());        if (!originalResponse.headers("Set-Cookie").isEmpty()) {            HashSet<String> cookies = new HashSet<>();            for (String header : originalResponse.headers("Set-Cookie")) {              cookies.add(header);            }            Preferences.getDefaultPreferences().edit()                    .putStringSet(Preferences.PREF_COOKIES, cookies)                    .apply();        }        return originalResponse;    }}

/** * Somewhere you create a new OkHttpClient and use it on all your requests. */OkHttpClient okHttpClient = new OkHttpClient();okHttpClient.interceptors().add(new AddCookiesInterceptor());okHttpClient.interceptors().add(new ReceivedCookiesInterceptor());