Android网络相关辅助类 NetUtils，androidnetutils, import andr

Android网络相关辅助类 NetUtils，androidnetutils, import andr

 import android.app.Activity;  import android.content.ComponentName;  import android.content.Context;  import android.content.Intent;  import android.net.ConnectivityManager;  import android.net.NetworkInfo;  /**  * 跟网络相关的工具类  *   *   *   */  public class NetUtils  {      private NetUtils()      {          /* cannot be instantiated */          throw new UnsupportedOperationException("cannot be instantiated");      }      /**      * 判断网络是否连接      *       * @param context      * @return      */      public static boolean isConnected(Context context)      {          ConnectivityManager connectivity = (ConnectivityManager) context                  .getSystemService(Context.CONNECTIVITY_SERVICE);          if (null != connectivity)          {              NetworkInfo info = connectivity.getActiveNetworkInfo();              if (null != info && info.isConnected())              {                  if (info.getState() == NetworkInfo.State.CONNECTED)                  {                      return true;                  }              }          }          return false;      }      /**      * 判断是否是wifi连接      */      public static boolean isWifi(Context context)      {          ConnectivityManager cm = (ConnectivityManager) context                  .getSystemService(Context.CONNECTIVITY_SERVICE);          if (cm == null)              return false;          return cm.getActiveNetworkInfo().getType() == ConnectivityManager.TYPE_WIFI;      }      /**      * 打开网络设置界面      */      public static void openSetting(Activity activity)      {          Intent intent = new Intent("/");          ComponentName cm = new ComponentName("com.android.settings",                  "com.android.settings.WirelessSettings");          intent.setComponent(cm);          intent.setAction("android.intent.action.VIEW");          activity.startActivityForResult(intent, 0);      }  }