参考：
android WebView的cookie机制
Android中Cookie获取、保存以及同步
OkHttp3实现Cookies持续化管理
1.先看一下Chrome中的Cookie信息
访问首页信息时：
1.第一次调用的Header信息
2.再次请求时Header信息
第一次请求时，服务器会在Response Header中带过来一个Set-Cookie,内容为JSESSIONID=C3E668A891BA4E1C160C91A7EBEAA540.h2;再次请求时，浏览器会在Requst Header中的Cookie将JSESSIONID带上。
在浏览器中调用登录接口时：
3.直接调用登录接口
4.打开首页后再调用登录接口
2.WebView的cookie机制
WebView是基于webkit内核的UI控件，相当于一个浏览器客户端。它会在本地维护每次会话的cookie(保存在data/data/package_name/app_WebView/Cookies.db)。如图：
查看APP cookie
当WebView加载URL的时候,WebView会从本地读取该URL对应的cookie，并携带该cookie与服务器进行通信。WebView通过android.webkit.CookieManager类来维护cookie。CookieManager是WebView的cookie管理类。
CookieManager.setCookie()方法:
/**
* Sets a cookie for the given URL. Any existing cookie with the same host,
* path and name will be replaced with the new cookie. The cookie being set
* must not have expired and must not be a session cookie, otherwise it
* will be ignored.
*
* @param url the URL for which the cookie is set
* @param value the cookie as a string, using the format of the 'Set-Cookie'
* HTTP response header
*/
public void setCookie(String url, String value) {
throw new MustOverrideException();
}
注：host、path和name相同的cookie 会被新的给替换掉，注意是host、path和name都相同的。url参数是你要为哪个cookie设置，而value和服务器返回设置sookie的方法'Set-Cookie‘是一致的。也就是一个url的多个cookie，要调用多次setCookie，而每一次调用value的值都类似于:
cookie + ";Max-Age=3600" + ";Domain=.163.com" + ";Path = /" // 当然还可以加上版本等信息
一般写法：
//value参数不要忘记加domain和path
cookieManager.setCookie(cookie.getDomain(), cookie.getName() + "=" + cookie.getValue() +
"; domain=" + cookie.getDomain() + "; path=" + cookie.getPath());
注意这里为什么第一个参数写了个cookie.getDomain()，而不是像api里边说的url这涉及到了cookie的知识，设置cookie时，会先检测cookie的Domain是否和url网址的域名一致，如果不一致设置cookie失败。所以url在里边起到作用，就是检测Domain域名。
注意，只有cookie的domain和path与请求的URL匹配才会发送这个cookie，所以设置cookie的时候value参数不要忘记加domain和path，如上面代码。
如何做：
下面我们就通过CookieManager将cookie同步到WebView中。之前同步cookie需要用到CookieSyncManager类，现在这个类已经被deprecated。如今WebView已经可以在需要的时候自动同步cookie了，所以不再需要创建CookieSyncManager类的对象来进行强制性的同步cookie了。现在只需要获得 CookieManager的对象将cookie设置进去就可以了。
第一步：登录时从服务器的返回头中取出cookie根据Http请求的客户端不同，取cookie的方式也不同，以HttpURLcollection为例：
String cookieStr = conn.getHeaderField("Set-Cookie");第二步：将cookie同步到WebView中
/**
* 将cookie同步到WebView
* @param url WebView要加载的url
* @param cookie 要同步的cookie
* @return true 同步cookie成功，false同步cookie失败
* @Author JPH
*/
public static boolean syncCookie(String url,String cookie) {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
CookieSyncManager.createInstance(context);
}
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.setCookie(url, cookie);//如果没有特殊需求，这里只需要将session id以"key=value"形式作为cookie即可
String newCookie = cookieManager.getCookie(url);
return TextUtils.isEmpty(newCookie)?false:true;
}
如果设置成功，通过cookieManager.getCookie(url)方法就可取得刚才设置的cookie，下面我们查看一下Cookie数据库中发生的变化。如图：
查看WebView cookie
3. OkHttp 中实现 Cookie 持久化管理
在OkHttp3中，对cookie而言，新增了两个类 Cookiejar 、 Cookie 两个类，在了解这两个类之前，先去看一下 HttpEngine 关于cookie管理的变化
private Request networkRequest(Request request) throws IOException {
Request.Builder result = request.newBuilder();
....
List cookies = client.cookieJar().loadForRequest(request.url());
if (!cookies.isEmpty()) {
result.header("Cookie", cookieHeader(cookies));
}
....
return result.build();
}
private String cookieHeader(List cookies) {
StringBuilder cookieHeader = new StringBuilder();
for (int i = 0, size = cookies.size(); i < size; i++) {
if (i > 0) {
cookieHeader.append("; ");
}
Cookie cookie = cookies.get(i);
cookieHeader.append(cookie.name()).append('=').append(cookie.value());
}
return cookieHeader.toString();
}
public void receiveHeaders(Headers headers) throws IOException {
if (client.cookieJar() == CookieJar.NO_COOKIES) return;
List cookies = Cookie.parseAll(userRequest.url(), headers);
if (cookies.isEmpty()) return;
client.cookieJar().saveFromResponse(userRequest.url(), cookies);
}
通过以上几个关键方法，可以很明显的感觉到作者的意图了，为了更加自由定制化的cookie管理。其中 loadForRequest() 、 saveFromResponse() 这两个方法最为关键，分别是在发送时向request header中加入cookie，在接收时，读取response header中的
Cookies持久化对Cookies持久化的方案，与之前版本并无很大区别，还是参考 android-async-http 这个库，主要参考其中两个类:
- PersistentCookieStore
- SerializableHttpCookie
与之前版本的区别是要将对 java.net.HttpCookie 这个类的缓存处理换成对 okhttp3.Cookie 的处理，其他方面几乎一样。
SerializableOkHttpCookies
主要做两件事：将Cookie对象输出为ObjectStream
将ObjectStream序列化成Cookie对象
public class SerializableOkHttpCookies implements Serializable {
private transient final Cookie cookies;
private transient Cookie clientCookies;
public SerializableOkHttpCookies(Cookie cookies) {
this.cookies = cookies;
}
public Cookie getCookies() {
Cookie bestCookies = cookies;
if (clientCookies != null) {
bestCookies = clientCookies;
}
return bestCookies;
}
private void writeObject(ObjectOutputStream out) throws IOException {
out.writeObject(cookies.name());
out.writeObject(cookies.value());
out.writeLong(cookies.expiresAt());
out.writeObject(cookies.domain());
out.writeObject(cookies.path());
out.writeBoolean(cookies.secure());
out.writeBoolean(cookies.httpOnly());
out.writeBoolean(cookies.hostOnly());
out.writeBoolean(cookies.persistent());
}
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
String name = (String) in.readObject();
String value = (String) in.readObject();
long expiresAt = in.readLong();
String domain = (String) in.readObject();
String path = (String) in.readObject();
boolean secure = in.readBoolean();
boolean httpOnly = in.readBoolean();
boolean hostOnly = in.readBoolean();
boolean persistent = in.readBoolean();
Cookie.Builder builder = new Cookie.Builder();
builder = builder.name(name);
builder = builder.value(value);
builder = builder.expiresAt(expiresAt);
builder = hostOnly ? builder.hostOnlyDomain(domain) : builder.domain(domain);
builder = builder.path(path);
builder = secure ? builder.secure() : builder;
builder = httpOnly ? builder.httpOnly() : builder;
clientCookies = builder.build();
}
}
PersistentCookieStore
根据一定的规则去缓存或者获取Cookie
SharedPreferences 存储
public class PersistentCookieStore {
private static final String LOG_TAG = "PersistentCookieStore";
private static final String COOKIE_PREFS = "Cookies_Prefs";
private final Map> cookies;
private final SharedPreferences cookiePrefs;
public PersistentCookieStore(Context context) {
cookiePrefs = context.getSharedPreferences(COOKIE_PREFS, 0);
cookies = new HashMap<>();
//将持久化的cookies缓存到内存中 即map cookies
Map prefsMap = cookiePrefs.getAll();
for (Map.Entry entry : prefsMap.entrySet()) {
String[] cookieNames = TextUtils.split((String) entry.getValue(), ",");
for (String name : cookieNames) {
String encodedCookie = cookiePrefs.getString(name, null);
if (encodedCookie != null) {
Cookie decodedCookie = decodeCookie(encodedCookie);
if (decodedCookie != null) {
if (!cookies.containsKey(entry.getKey())) {
cookies.put(entry.getKey(), new ConcurrentHashMap());
}
cookies.get(entry.getKey()).put(name, decodedCookie);
}
}
}
}
}
protected String getCookieToken(Cookie cookie) {
return cookie.name() + "@" + cookie.domain();
}
public void add(HttpUrl url, Cookie cookie) {
String name = getCookieToken(cookie);
//将cookies缓存到内存中 如果缓存过期 就重置此cookie
if (!cookie.persistent()) {
if (!cookies.containsKey(url.host())) {
cookies.put(url.host(), new ConcurrentHashMap());
}
cookies.get(url.host()).put(name, cookie);
} else {
if (cookies.containsKey(url.host())) {
cookies.get(url.host()).remove(name);
}
}
//讲cookies持久化到本地
SharedPreferences.Editor prefsWriter = cookiePrefs.edit();
prefsWriter.putString(url.host(), TextUtils.join(",", cookies.get(url.host()).keySet()));
prefsWriter.putString(name, encodeCookie(new SerializableOkHttpCookies(cookie)));
prefsWriter.apply();
}
public List get(HttpUrl url) {
ArrayList ret = new ArrayList<>();
if (cookies.containsKey(url.host()))
ret.addAll(cookies.get(url.host()).values());
return ret;
}
public boolean removeAll() {
SharedPreferences.Editor prefsWriter = cookiePrefs.edit();
prefsWriter.clear();
prefsWriter.apply();
cookies.clear();
return true;
}
public boolean remove(HttpUrl url, Cookie cookie) {
String name = getCookieToken(cookie);
if (cookies.containsKey(url.host()) && cookies.get(url.host()).containsKey(name)) {
cookies.get(url.host()).remove(name);
SharedPreferences.Editor prefsWriter = cookiePrefs.edit();
if (cookiePrefs.contains(name)) {
prefsWriter.remove(name);
}
prefsWriter.putString(url.host(), TextUtils.join(",", cookies.get(url.host()).keySet()));
prefsWriter.apply();
return true;
} else {
return false;
}
}
public List getCookies() {
ArrayList ret = new ArrayList<>();
for (String key : cookies.keySet())
ret.addAll(cookies.get(key).values());
return ret;
}
/**
* cookies 序列化成 string
*
* @param cookie 要序列化的cookie
* @return 序列化之后的string
*/
protected String encodeCookie(SerializableOkHttpCookies cookie) {
if (cookie == null)
return null;
ByteArrayOutputStream os = new ByteArrayOutputStream();
try {
ObjectOutputStream outputStream = new ObjectOutputStream(os);
outputStream.writeObject(cookie);
} catch (IOException e) {
Log.d(LOG_TAG, "IOException in encodeCookie", e);
return null;
}
return byteArrayToHexString(os.toByteArray());
}
/**
* 将字符串反序列化成cookies
*
* @param cookieString cookies string
* @return cookie object
*/
protected Cookie decodeCookie(String cookieString) {
byte[] bytes = hexStringToByteArray(cookieString);
ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(bytes);
Cookie cookie = null;
try {
ObjectInputStream objectInputStream = new ObjectInputStream(byteArrayInputStream);
cookie = ((SerializableOkHttpCookies) objectInputStream.readObject()).getCookies();
} catch (IOException e) {
Log.d(LOG_TAG, "IOException in decodeCookie", e);
} catch (ClassNotFoundException e) {
Log.d(LOG_TAG, "ClassNotFoundException in decodeCookie", e);
}
return cookie;
}
/**
* 二进制数组转十六进制字符串
*
* @param bytes byte array to be converted
* @return string containing hex values
*/
protected String byteArrayToHexString(byte[] bytes) {
StringBuilder sb = new StringBuilder(bytes.length * 2);
for (byte element : bytes) {
int v = element & 0xff;
if (v < 16) {
sb.append('0');
}
sb.append(Integer.toHexString(v));
}
return sb.toString().toUpperCase(Locale.US);
}
/**
* 十六进制字符串转二进制数组
*
* @param hexString string of hex-encoded values
* @return decoded byte array
*/
protected byte[] hexStringToByteArray(String hexString) {
int len = hexString.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i + 1), 16));
}
return data;
}
}
最终效果
完成对Cookie持久化之后，就可以对Cookiejar进行进一步修改了，最终效果：
/* 自动管理Cookies */
private class CookiesManager implements CookieJar {
private final PersistentCookieStore cookieStore = new PersistentCookieStore(getApplicationContext());
@Override
public void saveFromResponse(HttpUrl url, List cookies) {
if (cookies != null && cookies.size() > 0) {
for (Cookie item : cookies) {
cookieStore.add(url, item);
}
}
}
@Override
public List loadForRequest(HttpUrl url) {
List cookies = cookieStore.get(url);
return cookies;
}
}
最后设置OkHttpClient
//持久化管理
OkHttpClient.Builder builder = new OkHttpClient.Builder();
Cookiebuilder.cookieJar(new CookiesManager());