Update: with Hibernate 5 I was able to get more cross database compatible UUID's included (note: I am not the implementor, though I did give it a stab).
@Entity
public class MyEntity {
@Id
@GeneratedValue
@Column( columnDefinition = "uuid", updatable = false )
public UUID getId() {
return id;
}
}
Original
Dzone posted an article about a second version of the UUID generator last year
first create your own usertype (at least until hibernate implements similar)
public class UUIDType extends AbstractSingleColumnStandardBasicType<UUID> {
public static final String NAME = "uuid-name";
public static final UUIDType INSTANCE = new UUIDType();
public UUIDType() {
super( UUIDSqlTypeDescriptor.INSTANCE, UUIDTypeDescriptor.INSTANCE );
}
public String getName() {
return NAME;
}
public static class UUIDSqlTypeDescriptor implements SqlTypeDescriptor {
public static final UUIDSqlTypeDescriptor INSTANCE = new UUIDSqlTypeDescriptor();
public int getSqlType() {
// ugh
return Types.VARCHAR;
}
@Override
public boolean canBeRemapped() {
return true;
}
public <X> ValueBinder<X> getBinder( final JavaTypeDescriptor<X> javaTypeDescriptor ) {
return new BasicBinder<X>( javaTypeDescriptor, this ) {
@Override
protected void doBind( PreparedStatement st, X value, int index, WrapperOptions options )
throws SQLException {
st.setObject( index, javaTypeDescriptor.unwrap( value, UUID.class, options ) );
}
};
}
public <X> ValueExtractor<X> getExtractor( final JavaTypeDescriptor<X> javaTypeDescriptor ) {
return new BasicExtractor<X>( javaTypeDescriptor, this ) {
@Override
protected X doExtract( ResultSet rs, String name, WrapperOptions options ) throws SQLException {
return javaTypeDescriptor.wrap( rs.getObject( name ), options );
}
@Override
protected X doExtract( CallableStatement statement, int index, WrapperOptions options )
throws SQLException {
return javaTypeDescriptor.wrap( statement.getObject( index ), options );
}
@Override
protected X doExtract( CallableStatement statement, String name, WrapperOptions options )
throws SQLException {
return javaTypeDescriptor.wrap( statement.getObject( name ), options );
}
};
}
}
}
Then annotate your models package-info.java
@TypeDef(
name = UUIDType.NAME,
defaultForType = UUID.class,
typeClass = UUIDType.class
)
package com.xenoterracide.rpf.model;
import org.hibernate.annotations.TypeDef;
import org.hibernate.type.UUIDType;
import java.util.UUID;
finally in your entity
@Id
@Override
@GeneratedValue(generator = "uuid2")
@GenericGenerator(name = "uuid2", strategy = "uuid2")
@Column(name = "id", columnDefinition = "uuid")
public UUID getId() {
return id;
}
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