update DeviceInfo

src/main/java/com/common/toolbox/app_utils/DeviceInfo.java

@@ -13,11 +13,16 @@ import java.util.UUID;
  */
 public class DeviceInfo {
     private static final String SIGN_PATH = Environment.getExternalStorageDirectory() + "/sw_config/device.json";
+    public static String DEVICE_SIGN = "";
+    public static String SD_SIGN = "";
 
     /**
      * 读取SD卡中的设备指纹
      */
     public static String getDeviceSignFromSD() {
+        if (!TextUtils.isEmpty(SD_SIGN)) {
+            return SD_SIGN;
+        }
         String device_sign = "";
         File file = new File(SIGN_PATH);
         if (file.exists()) {
@@ -39,10 +44,11 @@ public class DeviceInfo {
         }
         //如果取不到就生成一个新的
         if (TextUtils.isEmpty(device_sign)) {
-            return writeSDSign();
-        } else {
-            return device_sign;
+            device_sign = writeSDSign();
         }
+
+        SD_SIGN = device_sign;
+        return SD_SIGN;
     }
 
     /**
@@ -76,7 +82,9 @@ public class DeviceInfo {
      * 根据硬件信息计算设备指纹
      */
     public static String getSignFromHardware() {
-
+        if (!TextUtils.isEmpty(DEVICE_SIGN)) {
+            return DEVICE_SIGN;
+        }
         String device_id = Build.BOARD + Build.BRAND +
                 Build.CPU_ABI + Build.DEVICE +
                 Build.DISPLAY + Build.HOST +
@@ -85,7 +93,8 @@ public class DeviceInfo {
                 Build.TAGS + Build.TYPE +
                 Build.USER;
 
-        return StringUtils.MD5(device_id);
+        DEVICE_SIGN = StringUtils.MD5(device_id);
+        return DEVICE_SIGN;
     }