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  • Android OkHttp的Cookie自己主动化管理

    Android中在使用OkHttp这个库的时候。有时候须要持久化Cookie,那么怎么实现呢。OkHttp的内部源代码过于复杂,不进行深究。这里仅仅看当中的HttpEngineer里面的部分源代码,在发起请求以及请求结束都会调用这个类的几个方法。

    我们先看networkRequest方法。在里面通过client.getCookieHandler()函数获得了CookieHandler对象。通过该对象拿到cookie并设置到请求头里,请求结束后取得响应后通过networkResponse.headers()函数将请求头获得传入receiveHeaders函数,并将取得的cookie存入getCookieHandler得到的一个CookieHandler对象中去

    /**
     * Populates request with defaults and cookies.
     *
     * <p>This client doesn't specify a default {@code Accept} header because it
     * doesn't know what content types the application is interested in.
     */
    private Request networkRequest(Request request) throws IOException {
      Request.Builder result = request.newBuilder();
    
      //此处省略n行代码......
    
      CookieHandler cookieHandler = client.getCookieHandler();
      if (cookieHandler != null) {
        // Capture the request headers added so far so that they can be offered to the CookieHandler.
        // This is mostly to stay close to the RI; it is unlikely any of the headers above would
        // affect cookie choice besides "Host".
        Map<String, List<String>> headers = OkHeaders.toMultimap(result.build().headers(), null);
    
        Map<String, List<String>> cookies = cookieHandler.get(request.uri(), headers);
    
        // Add any new cookies to the request.
        OkHeaders.addCookies(result, cookies);
      }
    
      //此处省略n行代码......
    
      return result.build();
    }
    public void readResponse() throws IOException {
      //此处省略n行代码......
    
      receiveHeaders(networkResponse.headers());
    
      //此处省略n行代码......
    }
    public void receiveHeaders(Headers headers) throws IOException {
      CookieHandler cookieHandler = client.getCookieHandler();
      if (cookieHandler != null) {
        cookieHandler.put(userRequest.uri(), OkHeaders.toMultimap(headers, null));
      }
    }

    而这个CookieHandler对象是OkHttpClient类中的一个属性,提供了getter和setter方法,默认的构造函数OkHttpClient client = new OkHttpClient();不会创建这个CookieHandler对象。如果我们传入了这个对象。那么OkHttp自然会进行cookie的自己主动管理了。

    private CookieHandler cookieHandler;
    public OkHttpClient setCookieHandler(CookieHandler cookieHandler) {
      this.cookieHandler = cookieHandler;
      return this;
    }
    
    public CookieHandler getCookieHandler() {
      return cookieHandler;
    }

    那么如果我们将CookieHandler对象传入

    OkHttpClient client = new OkHttpClient();
    client.setCookieHandler(CookieHandler cookieHanlder);

    那么,如今关键是怎样去实现这个CookieHandler 对象。CookieManager是CookieHandler 的一个子类,其构造函数 public CookieManager(CookieStore store, CookiePolicy cookiePolicy)须要传入两个參数,CookieStore 是一个接口,因此我们实现CookieStore接口中的抽象方法。就可以实现这个CookieHandler 对象。

    參考android-async-http这个库,它具有cookie的自己主动管理功能。主要我们參考当中的两个类

    參考以上两个类并做适当改动,得到了例如以下两个类,他们的功能就是将cookie保持在SharedPreferences中。

    package com.kltz88.okhttp.cookie;
    
    /**
     * User:lizhangqu(513163535@qq.com)
     * Date:2015-07-13
     * Time: 17:31
     */
    import java.io.IOException;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.io.Serializable;
    import java.net.HttpCookie;
    
    public class SerializableHttpCookie implements Serializable {
        private static final long serialVersionUID = 6374381323722046732L;
    
        private transient final HttpCookie cookie;
        private transient HttpCookie clientCookie;
    
        public SerializableHttpCookie(HttpCookie cookie) {
            this.cookie = cookie;
        }
    
        public HttpCookie getCookie() {
            HttpCookie bestCookie = cookie;
            if (clientCookie != null) {
                bestCookie = clientCookie;
            }
            return bestCookie;
        }
    
        private void writeObject(ObjectOutputStream out) throws IOException {
            out.writeObject(cookie.getName());
            out.writeObject(cookie.getValue());
            out.writeObject(cookie.getComment());
            out.writeObject(cookie.getCommentURL());
            out.writeObject(cookie.getDomain());
            out.writeLong(cookie.getMaxAge());
            out.writeObject(cookie.getPath());
            out.writeObject(cookie.getPortlist());
            out.writeInt(cookie.getVersion());
            out.writeBoolean(cookie.getSecure());
            out.writeBoolean(cookie.getDiscard());
        }
    
        private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
            String name = (String) in.readObject();
            String value = (String) in.readObject();
            clientCookie = new HttpCookie(name, value);
            clientCookie.setComment((String) in.readObject());
            clientCookie.setCommentURL((String) in.readObject());
            clientCookie.setDomain((String) in.readObject());
            clientCookie.setMaxAge(in.readLong());
            clientCookie.setPath((String) in.readObject());
            clientCookie.setPortlist((String) in.readObject());
            clientCookie.setVersion(in.readInt());
            clientCookie.setSecure(in.readBoolean());
            clientCookie.setDiscard(in.readBoolean());
        }
    }
    package com.kltz88.okhttp.cookie;
    
    /**
     * User:lizhangqu(513163535@qq.com)
     * Date:2015-07-13
     * Time: 17:31
     */
    import android.content.Context;
    import android.content.SharedPreferences;
    import android.text.TextUtils;
    import android.util.Log;
    
    import java.io.*;
    import java.net.CookieStore;
    import java.net.HttpCookie;
    import java.net.URI;
    import java.net.URISyntaxException;
    import java.util.*;
    import java.util.concurrent.ConcurrentHashMap;
    
    /**
     * A persistent cookie store which implements the Apache HttpClient CookieStore interface.
     * Cookies are stored and will persist on the user's device between application sessions since they
     * are serialized and stored in SharedPreferences. Instances of this class are
     * designed to be used with AsyncHttpClient#setCookieStore, but can also be used with a
     * regular old apache HttpClient/HttpContext if you prefer.
     */
    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<String, ConcurrentHashMap<String, HttpCookie>> 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<String, ConcurrentHashMap<String, HttpCookie>>();
    
            // Load any previously stored cookies into the store
            Map<String, ?> prefsMap = cookiePrefs.getAll();
            for(Map.Entry<String, ?

    > 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<String, HttpCookie>()); 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<String, HttpCookie>()); 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.commit(); } protected String getCookieToken(URI uri, HttpCookie cookie) { return cookie.getName() + cookie.getDomain(); } @Override public List<HttpCookie> get(URI uri) { ArrayList<HttpCookie> ret = new ArrayList<HttpCookie>(); 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.commit(); 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.commit(); return true; } else { return false; } } @Override public List<HttpCookie> getCookies() { ArrayList<HttpCookie> ret = new ArrayList<HttpCookie>(); for (String key : cookies.keySet()) ret.addAll(cookies.get(key).values()); return ret; } @Override public List<URI> getURIs() { ArrayList<URI> ret = new ArrayList<URI>(); 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) { Log.d(LOG_TAG, "IOException in encodeCookie", e); 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) { Log.d(LOG_TAG, "IOException in decodeCookie", e); } catch (ClassNotFoundException e) { Log.d(LOG_TAG, "ClassNotFoundException in decodeCookie", e); } return cookie; } /** * Using some super basic byte array &lt;-&gt; 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; } }

    使用的时候。在发起请求前对CookieHandler进行设置,兴许的cookie全都是自己主动管理,无需你关心cookie的保存于读取

    OkHttpClient client = new OkHttpClient();
    
    client.setCookieHandler(new CookieManager(
            new PersistentCookieStore(getApplicationContext()),
            CookiePolicy.ACCEPT_ALL));

    这样,实现模拟登录,抓取一些数据就方便非常多了。再也不用手动处理cookie了。

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  • 原文地址:https://www.cnblogs.com/tlnshuju/p/7171483.html
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