Ref
public
interface
Ref
| java.sql.Ref |
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:
Summary
Public methods | |
|---|---|
abstract
String
|
getBaseTypeName()
Retrieves the fully-qualified SQL name of the SQL structured type that
this |
abstract
Object
|
getObject()
Retrieves the SQL structured type instance referenced by
this |
abstract
Object
|
getObject(Map<String, Class<?>> map)
Retrieves the referenced object and maps it to a Java type using the given type map. |
abstract
void
|
setObject(Object value)
Sets the structured type value that this |
Public methods
getBaseTypeName
public abstract String getBaseTypeName ()
Retrieves the fully-qualified SQL name of the SQL structured type that
this Ref object references.
| Returns | |
|---|---|
String |
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 |
getObject
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 | |
|---|---|
Object |
a Java Object that is the mapping for
the SQL structured type to which this Ref
object refers |
| Throws | |
|---|---|
SQLException |
if a database access error occurs |
SQLFeatureNotSupportedException |
if the JDBC driver does not support this method |
See also:
getObject
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 |
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 | |
|---|---|
Object |
a Java Object that is the custom mapping for
the SQL structured type to which this Ref
object refers |
| Throws | |
|---|---|
SQLException |
if a database access error occurs |
SQLFeatureNotSupportedException |
if the JDBC driver does not support this method |
See also:
setObject
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 |
Object: 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 |