public AwsEc2SecurityGroupUserIdGroupPair withUserId(String userId) {
        setUserId(userId);
        return this;
    }
<p>
The ID of an Amazon Web Services account.
</p>
<p>
For a referenced security group in another VPC, the account ID of the referenced security group is returned in
the response. If the referenced security group is deleted, this value is not returned.
</p>
<p>
[EC2-Classic] Required when adding or removing rules that reference a security group in another VPC.
</p>

@param userId
       The ID of an Amazon Web Services account.</p>
       <p>
       For a referenced security group in another VPC, the account ID of the referenced security group is
       returned in the response. If the referenced security group is deleted, this value is not returned.
       </p>
       <p>
       [EC2-Classic] Required when adding or removing rules that reference a security group in another VPC.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-securityhub/src/main/java/com/amazonaws/services/securityhub/model/AwsEc2SecurityGroupUserIdGroupPair.java