@Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("{");
        if (getDeviceRegistrationState() != null)
            sb.append("DeviceRegistrationState: ").append(getDeviceRegistrationState()).append(",");
        if (getProximity() != null)
            sb.append("Proximity: ").append(getProximity()).append(",");
        if (getJoin() != null)
            sb.append("Join: ").append(getJoin()).append(",");
        if (getConnectionStatus() != null)
            sb.append("ConnectionStatus: ").append(getConnectionStatus()).append(",");
        if (getMessageDeliveryStatus() != null)
            sb.append("MessageDeliveryStatus: ").append(getMessageDeliveryStatus());
        sb.append("}");
        return sb.toString();
    }
Returns a string representation of this object. This is useful for testing and debugging. Sensitive data will be
redacted from this string using a placeholder value.

@return A string representation of this object.

@see java.lang.Object#toString()
aws-java-sdk-iotwireless/src/main/java/com/amazonaws/services/iotwireless/model/EventNotificationItemConfigurations.java