public interface SQLData
SQLData interface will be entered in the
appropriate Connection object's type map along with the SQL
name of the UDT for which it is a custom mapping.
Typically, a SQLData implementation
will define a field for each attribute of an SQL structured type or a
single field for an SQL DISTINCT type. When the UDT is
retrieved from a data source with the ResultSet.getObject
method, it will be mapped as an instance of this class. A programmer
can operate on this class instance just as on any other object in the
Java programming language and then store any changes made to it by
calling the PreparedStatement.setObject method,
which will map it back to the SQL type.
It is expected that the implementation of the class for a custom
mapping will be done by a tool. In a typical implementation, the
programmer would simply supply the name of the SQL UDT, the name of
the class to which it is being mapped, and the names of the fields to
which each of the attributes of the UDT is to be mapped. The tool will use
this information to implement the SQLData.readSQL and
SQLData.writeSQL methods. The readSQL method
calls the appropriate SQLInput methods to read
each attribute from an SQLInput object, and the
writeSQL method calls SQLOutput methods
to write each attribute back to the data source via an
SQLOutput object.
An application programmer will not normally call SQLData methods
directly, and the SQLInput and SQLOutput methods
are called internally by SQLData methods, not by application code.
| Modifier and Type | Method and Description |
|---|---|
String |
getSQLTypeName()
Returns the fully-qualified
name of the SQL user-defined type that this object represents.
|
void |
readSQL(SQLInput stream,
String typeName)
Populates this object with data read from the database.
|
void |
writeSQL(SQLOutput stream)
Writes this object to the given SQL data stream, converting it back to
its SQL value in the data source.
|
String getSQLTypeName() throws SQLException
SQLData.readSQL
when this object was constructed and populatedSQLException - if there is a database access errorSQLFeatureNotSupportedException - if the JDBC driver does not support
this methodvoid readSQL(SQLInput stream, String typeName) throws SQLException
readSQL then
assigns the data to appropriate fields or
elements (of this or other objects).
Specifically, it must call the appropriate reader method
(SQLInput.readString, SQLInput.readBigDecimal,
and so on) method(s) to do the following:
for a distinct type, read its single data element;
for a structured type, read a value for each attribute of the SQL type.
SQLInput reader method on the stream.stream - the SQLInput object from which to read the data for
the value that is being custom mappedtypeName - the SQL type name of the value on the data streamSQLException - if there is a database access errorSQLFeatureNotSupportedException - if the JDBC driver does not support
this methodSQLInputvoid writeSQL(SQLOutput stream) throws SQLException
SQLOutput writer
method(s) (writeInt, writeString, and so on)
to do the following: for a Distinct Type, write its single data element;
for a Structured Type, write a value for each attribute of the SQL type.stream - the SQLOutput object to which to write the data for
the value that was custom mappedSQLException - if there is a database access errorSQLFeatureNotSupportedException - if the JDBC driver does not support
this methodSQLOutput Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2020, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.