The mapping in the Java programming language of an SQL REF
value, which is a reference to an SQL structured type value in the database.
SQL REF
values are stored in a table that contains
instances of a referenceable SQL structured type, and each REF
value is a unique identifier for one instance in that table.
An SQL REF
value may be used in place of the
SQL structured type it references, either as a column value in a
table or an attribute value in a structured type.
Because an SQL REF
value is a logical pointer to an
SQL structured type, a Ref
object is by default also a logical
pointer. Thus, retrieving an SQL REF
value as
a Ref
object does not materialize
the attributes of the structured type on the client.
A Ref
object can be stored in the database using the
PreparedStatement.setRef
method.
All methods on the Ref
interface must be fully implemented if the
JDBC driver supports the data type.
See Also
Public Method Summary
abstract String |
getBaseTypeName()
Retrieves the fully-qualified SQL name of the SQL structured type that
this
Ref object references. |
abstract Object |
getObject()
Retrieves the SQL structured type instance referenced by
this
Ref object. |
abstract Object | |
abstract void |
Public Methods
public abstract String getBaseTypeName ()
Retrieves the fully-qualified SQL name of the SQL structured type that
this Ref
object references.
Returns
- the fully-qualified SQL name of the referenced SQL structured type
Throws
SQLException | if a database access error occurs |
---|---|
SQLFeatureNotSupportedException | if the JDBC driver does not support this method |
public abstract Object getObject ()
Retrieves the SQL structured type instance referenced by
this Ref
object. If the connection's type map has an entry
for the structured type, the instance will be custom mapped to
the Java class indicated in the type map. Otherwise, the
structured type instance will be mapped to a Struct
object.
Returns
- a Java
Object
that is the mapping for the SQL structured type to which thisRef
object refers
Throws
SQLException | if a database access error occurs |
---|---|
SQLFeatureNotSupportedException | if the JDBC driver does not support this method |
See Also
public abstract Object getObject (Map<String, Class<?>> map)
Retrieves the referenced object and maps it to a Java type using the given type map.
Parameters
map | a java.util.Map object that contains
the mapping to use (the fully-qualified name of the SQL
structured type being referenced and the class object for
SQLData implementation to which the SQL
structured type will be mapped) |
---|
Returns
- a Java
Object
that is the custom mapping for the SQL structured type to which thisRef
object refers
Throws
SQLException | if a database access error occurs |
---|---|
SQLFeatureNotSupportedException | if the JDBC driver does not support this method |
See Also
public abstract void setObject (Object value)
Sets the structured type value that this Ref
object references to the given instance of Object
.
The driver converts this to an SQL structured type when it
sends it to the database.
Parameters
value | an Object representing the SQL
structured type instance that this
Ref object will reference |
---|
Throws
SQLException | if a database access error occurs |
---|---|
SQLFeatureNotSupportedException | if the JDBC driver does not support this method |