@Override
		public boolean contains(Object o) {
			if (o == null) {
				return false;
			}
			try {
				@SuppressWarnings("unchecked")
				Node n = (Node) o;
				Node m = nodeMap.get(n.key);
				return Objects.equals(n.val, m.val);
			}
			catch (ClassCastException e) {
				return false;
			}
		}
Inserts (by copy) the entry into the owning map
Ghidra/Framework/Generic/src/main/java/ghidra/generic/util/datastruct/TreeValueSortedMap.java