public Number parseIntegral(final GremlinParser.IntegerLiteralContext integerLiteral) {
        return (Number) visitIntegerLiteral(integerLiteral);
    }
Parse integral literal context and return an integral type number.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/language/grammar/GenericLiteralVisitor.java