| This annotation specifies the version field or property of
an entity class that serves as its optimistic lock value.
The version is used to ensure integrity when performing the
merge operation and for optimistic concurrency control.
Only a single Version property or field
should be used per class; applications that use more than one
Version property or field will not be portable.
The Version property should be mapped to
the primary table for the entity class; applications that
map the Version property to a table other than
the primary table will not be portable.
The following types are supported for version properties:
int,
Integer , short,
Short , long,
Long ,
java.sql.Timestamp Timestamp .
Example:
@Version
@Column(name="OPTLOCK")
protected int getVersionNum() { return versionNum; }
since:
Java Persistence 1.0 |