public NotificationRecipientType withUserIds(String... userIds) {
        if (this.userIds == null) {
            setUserIds(new java.util.ArrayList<String>(userIds.length));
        }
        for (String ele : userIds) {
            this.userIds.add(ele);
        }
        return this;
    }
<p>
A list of user IDs.
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setUserIds(java.util.Collection)} or {@link #withUserIds(java.util.Collection)} if you want to override
the existing values.
</p>

@param userIds
       A list of user IDs.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-connect/src/main/java/com/amazonaws/services/connect/model/NotificationRecipientType.java