Type Conversion

How BoxLang's dynamic types are bridged to JDBC column types

BoxLang is dynamically typed, but JDBC and Hibernate expect a specific Java type for every column. bx-orm bridges the two using a set of built-in JPA AttributeConverter classes, applied automatically based on each property's ormType.

How It Works

When bx-orm generates the Hibernate mapping XML for a property, it normalizes the property's ormType value (folding aliases like big_decimal/bigdecimal, or date/datetime, down to a canonical name) and, for most properties, wires up a matching converter:

ormType values (aliases folded)	Canonical type	Converter used
string, varchar, nvarchar	string	StringConverter
bigdecimal, big_decimal, big-decimal	bigdecimal	BigDecimalConverter
biginteger, big_integer, big-integer, bigint	biginteger	BigIntegerConverter
integer, int	integer	IntegerConverter
long	long	LongConverter
tinyint, tinyinteger	short	ShortConverter
numeric, number, decimal	double	DoubleConverter
float	float	FloatConverter
bit, bool	boolean	BooleanConverter
yes-no, yesno, yes_no	yes_no	BooleanConverter
true-false, truefalse, true_false	true_false	BooleanConverter
eurodate, usdate, date, datetime	timestamp	DateTimeConverter
time	time	TimeConverter
blob, byte[]	binary	(none - stored as raw binary)
char, nchar	character	(none - stored as a single character)
clob	text	(none - stored as text)

Each converter's job is to translate a BoxLang dynamic value into the JDBC type Hibernate expects on the way into the database, and back into a BoxLang-friendly value on the way out - using BoxLang's own type casters (e.g. DateTimeCaster, so a DateTime object round-trips correctly regardless of what dynamic type was assigned to the property in memory).

Identifier and version properties skip converters. A property with fieldtype="id" or fieldtype="version" is written using its plain Hibernate basic type, not one of the converters above. This keeps primary key and optimistic-locking columns on Hibernate's native type handling.

Custom Converters

There is currently no supported mechanism for registering your own AttributeConverter for a property - the converters above are applied automatically based on ormType and cover the standard Hibernate basic types. If you need a database column type not covered here, use sqlType to control the generated DDL, or reach for a custom Hibernate config / hibernateProperties for engine-level tuning.

See Properties for the full list of ormType values you can set on a property.