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You can use getChildren() to get the collection of children's item IDs, over which you can iterate. I don't think you can access the generated checkboxes through the TreeTable's API. I'll assume that the checkboxes are not generated from the container properties. You could store references to them in a HashMap<Object,CheckBox> by using the item ID as the key; add the CheckBox references there in the column generator and remove them in a DetachListener added to each CheckBox.