public Builder removeNodeFlag(final NodeFlag nodeFlag) {
            if (nodeFlag != null && NullSafe.hasItems(this.nodeFlags)) {
                this.nodeFlags.remove(nodeFlag);
            }
            return this;
        }
Adds a flag to this node if nodeFlag is not null.
stroom-core-shared/src/main/java/stroom/explorer/shared/ExplorerNode.java