public void setCreatedAt(java.util.Date createdAt) {
        this.createdAt = createdAt;
    }
<p>
The Unix epoch timestamp in seconds for when the resource was created.
</p>

@param createdAt
       The Unix epoch timestamp in seconds for when the resource was created.
aws-java-sdk-appmesh/src/main/java/com/amazonaws/services/appmesh/model/RouteRef.java