- import android.content.Context;
- import android.content.SharedPreferences;
- import android.provider.Settings.Secure;
- import android.telephony.TelephonyManager;
- import java.io.UnsupportedEncodingException;
- import java.util.UUID;
- public class DeviceUuidFactory {
- protected static final String PREFS_FILE = "device_id.xml";
- protected static final String PREFS_DEVICE_ID = "device_id";
- protected static UUID uuid;
- public DeviceUuidFactory(Context context) {
- if( uuid ==null ) {
- synchronized (DeviceUuidFactory.class) {
- if( uuid == null) {
- final SharedPreferences prefs = context.getSharedPreferences( PREFS_FILE, 0);
- final String id = prefs.getString(PREFS_DEVICE_ID, null );
- if (id != null) {
- // Use the ids previously computed and stored in the prefs file
- uuid = UUID.fromString(id);
- } else {
- final String androidId = Secure.getString(context.getContentResolver(), Secure.ANDROID_ID);
- // Use the Android ID unless it's broken, in which case fallback on deviceId,
- // unless it's not available, then fallback on a random number which we store
- // to a prefs file
- try {
- if (!"9774d56d682e549c".equals(androidId)) {
- uuid = UUID.nameUUIDFromBytes(androidId.getBytes("utf8"));
- } else {
- final String deviceId = ((TelephonyManager) context.getSystemService( Context.TELEPHONY_SERVICE )).getDeviceId();
- uuid = deviceId!=null ? UUID.nameUUIDFromBytes(deviceId.getBytes("utf8")) : UUID.randomUUID();
- }
- } catch (UnsupportedEncodingException e) {
- throw new RuntimeException(e);
- }
- // Write the value out to the prefs file
- prefs.edit().putString(PREFS_DEVICE_ID, uuid.toString() ).commit();
- }
- }
- }
- }
- }
- /**
- * Returns a unique UUID for the current android device. As with all UUIDs, this unique ID is "very highly likely"
- * to be unique across all Android devices. Much more so than ANDROID_ID is.
- *
- * The UUID is generated by using ANDROID_ID as the base key if appropriate, falling back on
- * TelephonyManager.getDeviceID() if ANDROID_ID is known to be incorrect, and finally falling back
- * on a random UUID that's persisted to SharedPreferences if getDeviceID() does not return a
- * usable value.
- *
- * In some rare circumstances, this ID may change. In particular, if the device is factory reset a new device ID
- * may be generated. In addition, if a user upgrades their phone from certain buggy implementations of Android 2.2
- * to a newer, non-buggy version of Android, the device ID may change. Or, if a user uninstalls your app on
- * a device that has neither a proper Android ID nor a Device ID, this ID may change on reinstallation.
- *
- * Note that if the code falls back on using TelephonyManager.getDeviceId(), the resulting ID will NOT
- * change after a factory reset. Something to be aware of.
- *
- * Works around a bug in Android 2.2 for many devices when using ANDROID_ID directly.
- *
- * @see http://code.google.com/p/android/issues/detail?id=10603
- *
- * @return a UUID that may be used to uniquely identify your device for most purposes.
- */
- public UUID getDeviceUuid() {
- return uuid;
- }
- }
- //该片段来自于http://www.codesnippet.cn/detail/0312201411163.html
来源: http://www.codesnippet.cn/detail/0312201411163.html