Hibernate - Mapping Types


When you prepare a Hibernate mapping document, you find that you map the 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