Android中Cookie的持久化（包含Volley的Cookie持久化）

Android网络请求中Cookie的持久化

以下有两种方法

• 第一种方法是针对Volley来实现的，这种方法比较简单，但是对于有多重类型的Request必须都要按照这种方式来处理，耦合度比较高。

• 第二种方法只要设置一次，之后所有的请求都会携带cookie。建议采用第二种方法

第一种方式：通过自定义Request对象来处理

Request对象是一个抽象类，其中有两个抽象方法。

• abstract protected Response parseNetworkResponse(NetworkResponse response)

• abstract protected void deliverResponse(T response) 不需要操作该方法

这两个方法经常被我们用来实现自定义的Request对象，而如果要实现Cookie的自定义这两个方法我们只需要使用到 第一个方法 parseNetworkResponse 和 public Map getHeaders() throws AuthFailureError方法。

import com.android.volley.AuthFailureError;
import com.android.volley.NetworkResponse;
import com.android.volley.Request;
import com.android.volley.Response;

import java.util.Map;

public class CustomStringRequest extends Request<String>{


    public CustomStringRequest(String url, Response.ErrorListener listener) {
        super(url, listener);
    }

    public CustomStringRequest(int method, String url, Response.ErrorListener listener) {
        super(method, url, listener);
    }


       @Override
    protected Response parseNetworkResponse(NetworkResponse response) {

            //在这里可以的到 response 对象， 然后从response的header中获取cookie信息
            if (headers.containsKey(SET_COOKIE_KEY)
                && headers.get(SET_COOKIE_KEY).startsWith(SESSION_COOKIE)) {
                String cookie = headers.get(SET_COOKIE_KEY);
                if (cookie.length() > 0) {
                    String[] splitCookie = cookie.split(";");
                    String[] splitSessionId = splitCookie[0].split("=");
                    cookie = splitSessionId[1];

                    //将得到的cookie存储到Sharepreference中
                    Editor prefEditor = _preferences.edit();
                    prefEditor.putString(SESSION_COOKIE, cookie);
                    prefEditor.commit();
                }
            }
        //------------------end-----------------------

        //加上自己的其他逻辑代码

        return null;
    }

     @Override
    public Map getHeaders() throws AuthFailureError {

            Map headers = super.getHeaders();

        if (headers == null
                || headers.equals(Collections.emptyMap())) {
            headers = new HashMap();
        }

        //从Sharepreference中获取到cookie，并把cookie添加到header中

        String sessionId = _preferences.getString(SESSION_COOKIE, "");
        if (sessionId.length() > 0) {
            StringBuilder builder = new StringBuilder();
            builder.append(SESSION_COOKIE);
            builder.append("=");
            builder.append(sessionId);
            if (headers.containsKey(COOKIE_KEY)) {
                builder.append("; ");
                builder.append(headers.get(COOKIE_KEY));
            }
            headers.put(COOKIE_KEY, builder.toString());
        }
            //-----------------end-------------------------

        return headers;

        //return super.getHeaders();
    }



    @Override
    protected void deliverResponse(String response) {

    }
}

通过在 parseNetworkResponse 和 getHeaders方法的自定义，就可以实现Request请求携带Cookie参数。

第二种方式：CookieManager 和自定义的CookieStore

CookieManager会帮我们管理本地Java应用的cookie，我们只需要实现自定义 CookieStore就能实现持久化的Cookie。

关于CookieManager的介绍和 CookieStore的自定义可以参考另外一篇文章。Android中Cookie的使用

晚上也会有一些实现好了的PersistCookieStore比如 这个

下面给出一个已经实现的自定义的持久化CookieStore

public class PersistentCookieStore implements CookieStore {

    private static final String LOG_TAG = "PersistentCookieStore";
    private static final String COOKIE_PREFS = "CookiePrefsFile";
    private static final String COOKIE_NAME_PREFIX = "cookie_";

    private final HashMap> cookies;
    private final SharedPreferences cookiePrefs;

    /**
     * Construct a persistent cookie store.
     *
     * @param context Context to attach cookie store to
     */
    public PersistentCookieStore(Context context) {
        cookiePrefs = context.getSharedPreferences(COOKIE_PREFS, 0);
        cookies = new HashMap>();

        // Load any previously stored cookies into the store
        Map prefsMap = cookiePrefs.getAll();
        for(Map.Entry entry : prefsMap.entrySet()) {
            if (((String)entry.getValue()) != null && !((String)entry.getValue()).startsWith(COOKIE_NAME_PREFIX)) {
                String[] cookieNames = TextUtils.split((String)entry.getValue(), ",");
                for (String name : cookieNames) {
                    String encodedCookie = cookiePrefs.getString(COOKIE_NAME_PREFIX + name, null);
                    if (encodedCookie != null) {
                        HttpCookie decodedCookie = decodeCookie(encodedCookie);
                        if (decodedCookie != null) {
                            if(!cookies.containsKey(entry.getKey()))
                                cookies.put(entry.getKey(), new ConcurrentHashMap());
                            cookies.get(entry.getKey()).put(name, decodedCookie);
                        }
                    }
                }

            }
        }
    }

    @Override
    public void add(URI uri, HttpCookie cookie) {
        String name = getCookieToken(uri, cookie);

        // Save cookie into local store, or remove if expired
        if (!cookie.hasExpired()) {
            if(!cookies.containsKey(uri.getHost()))
                cookies.put(uri.getHost(), new ConcurrentHashMap());
            cookies.get(uri.getHost()).put(name, cookie);
        } else {
            if(cookies.containsKey(uri.toString()))
                cookies.get(uri.getHost()).remove(name);
        }

        // Save cookie into persistent store
        SharedPreferences.Editor prefsWriter = cookiePrefs.edit();
        prefsWriter.putString(uri.getHost(), TextUtils.join(",", cookies.get(uri.getHost()).keySet()));
        prefsWriter.putString(COOKIE_NAME_PREFIX + name, encodeCookie(new SerializableHttpCookie(cookie)));
        prefsWriter.apply();
    }

    protected String getCookieToken(URI uri, HttpCookie cookie) {
        return cookie.getName() + cookie.getDomain();
    }

    @Override
    public List get(URI uri) {
        ArrayList ret = new ArrayList();
        if(cookies.containsKey(uri.getHost()))
            ret.addAll(cookies.get(uri.getHost()).values());
        return ret;
    }

    @Override
    public boolean removeAll() {
        SharedPreferences.Editor prefsWriter = cookiePrefs.edit();
        prefsWriter.clear();
        prefsWriter.apply();
        cookies.clear();
        return true;
    }


    @Override
    public boolean remove(URI uri, HttpCookie cookie) {
        String name = getCookieToken(uri, cookie);

        if(cookies.containsKey(uri.getHost()) && cookies.get(uri.getHost()).containsKey(name)) {
            cookies.get(uri.getHost()).remove(name);

            SharedPreferences.Editor prefsWriter = cookiePrefs.edit();
            if(cookiePrefs.contains(COOKIE_NAME_PREFIX + name)) {
                prefsWriter.remove(COOKIE_NAME_PREFIX + name);
            }
            prefsWriter.putString(uri.getHost(), TextUtils.join(",", cookies.get(uri.getHost()).keySet()));
            prefsWriter.apply();

            return true;
        } else {
            return false;
        }
    }

    @Override
    public List getCookies() {
        ArrayList ret = new ArrayList();
        for (String key : cookies.keySet())
            ret.addAll(cookies.get(key).values());

        return ret;
    }

    @Override
    public List getURIs() {
        ArrayList ret = new ArrayList();
        for (String key : cookies.keySet())
            try {
                ret.add(new URI(key));
            } catch (URISyntaxException e) {
                e.printStackTrace();
            }

        return ret;
    }

    /**
     * Serializes Cookie object into String
     *
     * @param cookie cookie to be encoded, can be null
     * @return cookie encoded as String
     */
    protected String encodeCookie(SerializableHttpCookie cookie) {
        if (cookie == null)
            return null;
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        try {
            ObjectOutputStream outputStream = new ObjectOutputStream(os);
            outputStream.writeObject(cookie);
        } catch (IOException e) {
            L.d(LOG_TAG, "IOException in encodeCookie " + e.toString());
            return null;
        }

        return byteArrayToHexString(os.toByteArray());
    }

    /**
     * Returns cookie decoded from cookie string
     *
     * @param cookieString string of cookie as returned from http request
     * @return decoded cookie or null if exception occured
     */
    protected HttpCookie decodeCookie(String cookieString) {
        byte[] bytes = hexStringToByteArray(cookieString);
        ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(bytes);
        HttpCookie cookie = null;
        try {
            ObjectInputStream objectInputStream = new ObjectInputStream(byteArrayInputStream);
            cookie = ((SerializableHttpCookie) objectInputStream.readObject()).getCookie();
        } catch (IOException e) {
            L.d(LOG_TAG, "IOException in decodeCookie " + e.toString());
        } catch (ClassNotFoundException e) {
            L.d(LOG_TAG, "ClassNotFoundException in decodeCookie " + e.toString());
        }

        return cookie;
    }

    /**
     * Using some super basic byte array <-> hex conversions so we don't have to rely on any
     * large Base64 libraries. Can be overridden if you like!
     *
     * @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);
    }

    /**
     * Converts hex values from strings to byte arra
     *
     * @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;
    }
}

这个CookieStore内部也是通过Sharepreference来实现cookie的持久化的。
现在定制好了自己的CookieStore，如何来进行设置然后使其生效呢？

      //init for api client sync cookie
        manager = new CookieManager(
                new PersistentCookieStore(context),
                CookiePolicy.ACCEPT_ALL);
        CookieHandler.setDefault(manager);

只要在网络请求之前调用这个方法，就可以将自定义的CookieStore设置到CookieManager中，CookieManager会在之后的HTTP请求中自动的帮我们处理response中cookie。

建议中Application启动的时候调用上面的设置代码。

CookiePolicy也是可以进行自定义的，详细可以参考另外一边文章。Android中Cookie的使用