content: //
  //  Copyright (c) 2014 VK.com
  //
  //  Permission is hereby granted, free of charge, to any person obtaining a copy of
  //  this software and associated documentation files (the "Software"), to deal in
  //  the Software without restriction, including without limitation the rights to
  //  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
  //  the Software, and to permit persons to whom the Software is furnished to do so,
  //  subject to the following conditions:
  //
  //  The above copyright notice and this permission notice shall be included in all
  //  copies or substantial portions of the Software.
  //
  //  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  //  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  //  FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  //  COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  //  IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  //  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  //
  
  package com.vk.sdk;
  
  import com.vk.sdk.api.VKError;
  
  /**
   * Global SDK events delegate interface.
   */
  public abstract class VKSdkListener {
  	/**
  	 * Calls when user must perform captcha-check
  	 * 
  	 * @param captchaError error returned from API. You can load captcha image from
  	 * <b>captchaImg</b> property. After user answered current
  	 * captcha, call answerCaptcha: method with user entered answer.
  	 */
  	public abstract void onCaptchaError(VKError captchaError);
  
  	/**
  	 * Notifies listener about existing token has expired
  	 * 
  	 * @param expiredToken old token that has expired
  	 */
  	public abstract void onTokenExpired(VKAccessToken expiredToken);
  
  	/**
  	 * Notifies listener about user authorization cancelation
  	 * 
  	 * @param authorizationError error that describes authorization error
  	 */
  	public abstract void onAccessDenied(VKError authorizationError);
  
  	/**
  	 * Notifies listener about receiving new access token
  	 * 
  	 * @param newToken new token for API requests
  	 */
  	public void onReceiveNewToken(VKAccessToken newToken) {
  	}
  
  	/**
  	 * Notifies listener about receiving predefined token
  	 * 
  	 * @param token used token for API requests
  	 */
  	public void onAcceptUserToken(VKAccessToken token) {
  	}
  
  	/**
  	 * Notifies listener about renewing access token (for example, user passed validation)
  	 *
  	 * @param token used token for API requests
  	 */
  	public void onRenewAccessToken(VKAccessToken token) {
  	}
  
  }
  