public void setUserGroups(java.util.Collection<String> userGroups) {
        if (userGroups == null) {
            this.userGroups = null;
            return;
        }

        this.userGroups = new com.amazonaws.internal.SdkInternalList<String>(userGroups);
    }
<p>
The user groups. This parameter can be used only when the <code>Attribute</code> parameter is
<code>launchPermission</code>.
</p>

@param userGroups
       The user groups. This parameter can be used only when the <code>Attribute</code> parameter is
       <code>launchPermission</code>.
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/model/ModifyImageAttributeRequest.java