How to determine if network type is 2G, 3G or 4G

You can put this following method directly in your Utility class:

Kotlin:

/** Usage: `networkTypeClass(telephonyManager.networkType)` */
fun networkTypeClass(networkType: Int): String {
    when (networkType) {
        TelephonyManager.NETWORK_TYPE_GPRS,
        TelephonyManager.NETWORK_TYPE_EDGE,
        TelephonyManager.NETWORK_TYPE_CDMA,
        TelephonyManager.NETWORK_TYPE_1xRTT,
        TelephonyManager.NETWORK_TYPE_IDEN,
        TelephonyManager.NETWORK_TYPE_GSM
        -> return "2G"
        TelephonyManager.NETWORK_TYPE_UMTS,
        TelephonyManager.NETWORK_TYPE_EVDO_0,
        TelephonyManager.NETWORK_TYPE_EVDO_A,
        TelephonyManager.NETWORK_TYPE_HSDPA,
        TelephonyManager.NETWORK_TYPE_HSUPA,
        TelephonyManager.NETWORK_TYPE_HSPA,
        TelephonyManager.NETWORK_TYPE_EVDO_B,
        TelephonyManager.NETWORK_TYPE_EHRPD,
        TelephonyManager.NETWORK_TYPE_HSPAP,
        TelephonyManager.NETWORK_TYPE_TD_SCDMA
        -> return "3G"
        TelephonyManager.NETWORK_TYPE_LTE
        -> return "4G"
        TelephonyManager.NETWORK_TYPE_NR
        -> return "5G"
        else -> return "Unknown"
    }
}

Java:

public String getNetworkClass(Context context) {
    TelephonyManager mTelephonyManager = (TelephonyManager)
            context.getSystemService(Context.TELEPHONY_SERVICE);
    int networkType = mTelephonyManager.getNetworkType();
    switch (networkType) {
        case TelephonyManager.NETWORK_TYPE_GPRS:
        case TelephonyManager.NETWORK_TYPE_EDGE:
        case TelephonyManager.NETWORK_TYPE_CDMA:
        case TelephonyManager.NETWORK_TYPE_1xRTT:
        case TelephonyManager.NETWORK_TYPE_IDEN:
            return "2G";
        case TelephonyManager.NETWORK_TYPE_UMTS:
        case TelephonyManager.NETWORK_TYPE_EVDO_0:
        case TelephonyManager.NETWORK_TYPE_EVDO_A:
        case TelephonyManager.NETWORK_TYPE_HSDPA:
        case TelephonyManager.NETWORK_TYPE_HSUPA:
        case TelephonyManager.NETWORK_TYPE_HSPA:
        case TelephonyManager.NETWORK_TYPE_EVDO_B:
        case TelephonyManager.NETWORK_TYPE_EHRPD:
        case TelephonyManager.NETWORK_TYPE_HSPAP:
            return "3G";
        case TelephonyManager.NETWORK_TYPE_LTE:
            return "4G";
        case TelephonyManager.NETWORK_TYPE_NR:
            return "5G";
        default:
            return "Unknown";
    }
}

Thanks to assistance from the Android source code. =]