@Override
    public ModifyVpnConnectionResult modifyVpnConnection(ModifyVpnConnectionRequest request) {
        request = beforeClientExecution(request);
        return executeModifyVpnConnection(request);
    }
<p>
Modifies the customer gateway or the target gateway of an Amazon Web Services Site-to-Site VPN connection. To
modify the target gateway, the following migration options are available:
</p>
<ul>
<li>
<p>
An existing virtual private gateway to a new virtual private gateway
</p>
</li>
<li>
<p>
An existing virtual private gateway to a transit gateway
</p>
</li>
<li>
<p>
An existing transit gateway to a new transit gateway
</p>
</li>
<li>
<p>
An existing transit gateway to a virtual private gateway
</p>
</li>
</ul>
<p>
Before you perform the migration to the new gateway, you must configure the new gateway. Use
<a>CreateVpnGateway</a> to create a virtual private gateway, or <a>CreateTransitGateway</a> to create a transit
gateway.
</p>
<p>
This step is required when you migrate from a virtual private gateway with static routes to a transit gateway.
</p>
<p>
You must delete the static routes before you migrate to the new gateway.
</p>
<p>
Keep a copy of the static route before you delete it. You will need to add back these routes to the transit
gateway after the VPN connection migration is complete.
</p>
<p>
After you migrate to the new gateway, you might need to modify your VPC route table. Use <a>CreateRoute</a> and
<a>DeleteRoute</a> to make the changes described in <a
href="https://docs.aws.amazon.com/vpn/latest/s2svpn/modify-vpn-target.html#step-update-routing">Update VPC route
tables</a> in the <i>Amazon Web Services Site-to-Site VPN User Guide</i>.
</p>
<p>
When the new gateway is a transit gateway, modify the transit gateway route table to allow traffic between the
VPC and the Amazon Web Services Site-to-Site VPN connection. Use <a>CreateTransitGatewayRoute</a> to add the
routes.
</p>
<p>
If you deleted VPN static routes, you must add the static routes to the transit gateway route table.
</p>
<p>
After you perform this operation, the VPN endpoint's IP addresses on the Amazon Web Services side and the tunnel
options remain intact. Your Amazon Web Services Site-to-Site VPN connection will be temporarily unavailable for a
brief period while we provision the new endpoints.
</p>

@param modifyVpnConnectionRequest
@return Result of the ModifyVpnConnection operation returned by the service.
@sample AmazonEC2.ModifyVpnConnection
@see <a href="http://docs.aws.amazon.com/goto/WebAPI/ec2-2016-11-15/ModifyVpnConnection" target="_top">AWS API
     Documentation</a>
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/AmazonEC2Client.java