public String getTransitGatewayId() {
        return this.transitGatewayId;
    }
<note>
<p>
This parameter is in preview and may not be available for your account.
</p>
</note>
<p>
The ID of the transit gateway (if applicable).
</p>

@return <p>
        This parameter is in preview and may not be available for your account.
        </p>
        </note>
        <p>
        The ID of the transit gateway (if applicable).
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/model/SecurityGroupReference.java