Okhttp3实现爬取验证码及获取Cookie的示例

compile'com.squareup.okhttp3:okhttp:3.5.0

<uses-permissionandroid:name="android.permission.INTERNET" />

  /**   * 初始化验证码   */  public void initCode(){    Request request = new Request.Builder().url(eduBean.getCodeUrl()).build();    Call call = okHttpClient.newCall(request);    call.enqueue(new Callback() {      @Override      public void onFailure(Call call, IOException e) {//        showToast("验证码加载失败");      }      @Override      public void onResponse(Call call, Response response) throws IOException {        byte[] byte_image = response.body().bytes();        //通过handler更新UI        Message message = handler.obtainMessage();        message.obj = byte_image;        message.what = 1;        handler.sendMessage(message);        //获取session的操作，session放在cookie头，且取出后含有“；”，取出后为下面的 s （也就是jsesseionid）        Headers headers = response.headers();//        Log.d("info_headers", "header " + headers);        List<String> cookies = headers.values("Set-Cookie");        String session = cookies.get(0);//        Log.d("info_cookies", "onResponse-size: " + cookies);        String sessionID = session.substring(0, session.indexOf(";"));        eduBean.setSessionID(sessionID);//        Log.i("info_s", "session is :" + sessionID);      }    });  }

public Handler handler = new Handler(){    public void handleMessage(Message msg){      switch (msg.what){        case 1:            //加载网络成功进行UI的更新,处理得到的图片资源            //通过message，拿到字节数组            byte[] Picture = (byte[]) msg.obj;            //使用BitmapFactory工厂，把字节数组转化为bitmap            Bitmap bitmap = BitmapFactory.decodeByteArray(Picture, 0, Picture.length);            //通过imageview，设置图片            iv_code.setImageBitmap(bitmap);//ImageView 显示验证码的组件            break;      }    }