public void setIpAddressType(String ipAddressType) {
        this.ipAddressType = ipAddressType;
    }
<p>
The IP address type for the instance.
</p>
<p>
The possible values are <code>ipv4</code> for IPv4 only, <code>ipv6</code> for IPv6 only, and
<code>dualstack</code> for IPv4 and IPv6.
</p>
<p>
The default value is <code>dualstack</code>.
</p>

@param ipAddressType
       The IP address type for the instance.</p>
       <p>
       The possible values are <code>ipv4</code> for IPv4 only, <code>ipv6</code> for IPv6 only, and
       <code>dualstack</code> for IPv4 and IPv6.
       </p>
       <p>
       The default value is <code>dualstack</code>.
@see IpAddressType
aws-java-sdk-lightsail/src/main/java/com/amazonaws/services/lightsail/model/CreateInstancesRequest.java