microsoft-azure-storage/src/com/microsoft/azure/storage/IPRange.java
private static void validateIPAddress(String ipAddress) {
        try {
            @SuppressWarnings("unused")
            Inet4Address address = (Inet4Address) Inet4Address.getByName(ipAddress);
        }
        catch (Exception ex) {
            throw new IllegalArgumentException(String.format(SR.INVALID_IP_ADDRESS, ipAddress), ex);
        }
    }
private static void validateIPAddress(String ipAddress) {
        try {
            @SuppressWarnings("unused")
            Inet4Address address = (Inet4Address) Inet4Address.getByName(ipAddress);
        }
        catch (Exception ex) {
            throw new IllegalArgumentException(String.format(SR.INVALID_IP_ADDRESS, ipAddress), ex);
        }
    }
Validate that the IP address is IPv4.

@param ipAddress
the IP address to validate