presto-main/src/main/java/io/prestosql/metadata/InternalNode.java/InternalNode/InternalNode
class InternalNode:    public InternalNode(String nodeIdentifier, URI internalUri, NodeVersion nodeVersion, boolean coordinator)
    {
        nodeIdentifier = emptyToNull(nullToEmpty(nodeIdentifier).trim());
        this.nodeIdentifier = requireNonNull(nodeIdentifier, "nodeIdentifier is null or empty");
        this.internalUri = requireNonNull(internalUri, "internalUri is null");
        this.nodeVersion = requireNonNull(nodeVersion, "nodeVersion is null");
        this.coordinator = coordinator;
    }