When you prepare a Hibernate mapping document, we have seen that you map Java data types into RDBMS data types. The
types
declared and used in the mapping files are not Java data types; they
are not SQL database types either. These types are called Hibernate
mapping types, which can translate from Java to SQL data types and vice
versa.
This chapter lists down all the basic, date and time, large object, and various other builtin mapping types.
Primitive types:
| Mapping type |
Java type |
ANSI SQL Type |
| integer |
int or java.lang.Integer |
INTEGER |
| long |
long or java.lang.Long |
BIGINT |
| short |
short or java.lang.Short |
SMALLINT |
| float |
float or java.lang.Float |
FLOAT |
| double |
double or java.lang.Double |
DOUBLE |
| big_decimal |
java.math.BigDecimal |
NUMERIC |
| character |
java.lang.String |
CHAR(1) |
| string |
java.lang.String |
VARCHAR |
| byte |
byte or java.lang.Byte |
TINYINT |
| boolean |
boolean or java.lang.Boolean |
BIT |
| yes/no |
boolean or java.lang.Boolean |
CHAR(1) ('Y' or 'N') |
| true/false |
boolean or java.lang.Boolean |
CHAR(1) ('T' or 'F') |
Date and time types:
| Mapping type |
Java type | ANSI SQL Type |
| date |
java.util.Date or java.sql.Date |
DATE |
| time |
java.util.Date or java.sql.Time |
TIME |
| timestamp |
java.util.Date or java.sql.Timestamp |
TIMESTAMP |
| calendar |
java.util.Calendar |
TIMESTAMP |
| calendar_date |
java.util.Calendar |
DATE |
Binary and large object types:
| Mapping type |
Java type | ANSI SQL Type |
| binary |
byte[] |
VARBINARY (or BLOB) |
| text |
java.lang.String |
CLOB |
| serializable |
any Java class that implements java.io.Serializable |
VARBINARY (or BLOB) |
| clob |
java.sql.Clob |
CLOB |
| blob |
java.sql.Blob |
BLOB |
JDK-related types:
| Mapping type |
Java type | ANSI SQL Type |
| class |
java.lang.Class |
VARCHAR |
| locale |
java.util.Locale |
VARCHAR |
| timezone |
java.util.TimeZone |
VARCHAR |
| currency |
java.util.Currency |
VARCHAR |