Standard JDBC RowSet implementations may use these utility
* classes to
* assist in the serialization of disconnected RowSet objects.
* This is useful
* when transmitting a disconnected RowSet object over the wire to
* a different VM or across layers within an application.
*
SerialArray class provides a constructor for creating a SerialArray
* instance from an Array object, methods for getting the base type and
* the SQL name for the base type, and methods for copying all or part of a
* SerialArray object. SerialBlobclass provides a constructor for creating an instance
* from a Blob object. Note that the Blob object should have brought the SQL
* BLOB value's data over to the client before a SerialBlobobject
* is constructed from it. The data of an SQL BLOB value can be materialized
* on the client as an array of bytes (using the method Blob.getBytes)
* or as a stream of uninterpreted bytes (using the method Blob.getBinaryStream).
* SerialBlob methods make it possible to make a copy of a SerialBlob
* object as an array of bytes or as a stream. They also make it possible
* to locate a given pattern of bytes or a Blob object within a SerialBlob
* object. SerialClob class provides a constructor for creating an instance
* from a Clob object. Note that the Clob object should have
* brought the SQL CLOB value's data over to the client before a SerialClob
* object is constructed from it. The data of an SQL CLOB value can be
* materialized on the client as a stream of Unicode characters. SerialClob methods make it possible to get a substring from a
* SerialClob object or to locate the start of a pattern of characters.
* RowSet implementations can use the method RowSet.getURL() to retrieve
* a java.net.URL object, which can be used to manipulate the external data.
* java.net.URL url = rowset.getURL(1);SerialException being thrown. SerialRef class provides a constructor for creating a SerialRef
* instance from a Ref type and provides methods for getting
* and setting the Ref object type. Map object is passed to one of the constructors or
* to the method getAttributes, the structured type is custom mapped
* according to the mapping specified in the Map object.
* SerialStruct class provides a constructor for creating an
* instance from a Struct object, a method for retrieving the SQL
* type name of the SQL structured type in the database, and methods for retrieving
* its attribute values. SQLInputImpl object is an input stream that contains a stream of
* values that are
* the attributes of a UDT. This class is used by the driver behind the scenes
* when the method getObject is called on an SQL structured or distinct
* type that has a custom mapping; a programmer never invokes SQLInputImpl
* methods directly. SQLInputImpl class provides a set of reader methods
* analogous to the ResultSet getter methods. These methods make it
* possible to read the values in an SQLInputImpl object. The method
* wasNull is used to determine whether the last value read was SQL NULL.
* Map object is called,
* the JDBC driver calls the method
* SQLData.getSQLType to determine the SQL type of the UDT being custom
* mapped. The driver creates an instance of SQLInputImpl, populating it with
* the attributes of the UDT. The driver then passes the input stream to the
* method SQLData.readSQL, which in turn calls the SQLInputImpl
* methods to read the attributes from the input stream. PreparedStatement.setObject, the
* driver checks to see whether the value to be written is a UDT with a custom
* mapping. If it is, there will be an entry in a type map containing the Class
* object for the class that implements SQLData for this UDT. If the
* value to be written is an instance of SQLData, the driver will
* create an instance of SQLOutputImpl and pass it to the method
* SQLData.writeSQL.
* The method writeSQL in turn calls the appropriate SQLOutputImpl
* writer methods to write data from the SQLData object to the
* SQLOutputImpl
* output stream as the representation of an SQL user-defined type.
*
*
* A programmer defines the mapping by implementing the interface SQLData.
* For example, if an SQL structured type named AUTHORS has the attributes NAME,
* TITLE, and PUBLISHER, it could be mapped to a Java class named Authors. The
* Authors class could have the fields name, title, and publisher, to which the
* attributes of AUTHORS are mapped. In such a case, the implementation of
* SQLData could look like the following:
*
* public class Authors implements SQLData {
* public String name;
* public String title;
* public String publisher;
*
* private String sql_type;
* public String getSQLTypeName() {
* return sql_type;
* }
*
* public void readSQL(SQLInput stream, String type)
* throws SQLException {
* sql_type = type;
* name = stream.readString();
* title = stream.readString();
* publisher = stream.readString();
* }
*
* public void writeSQL(SQLOutput stream) throws SQLException {
* stream.writeString(name);
* stream.writeString(title);
* stream.writeString(publisher);
* }
* }
*
*
* A java.util.Map object is used to associate the SQL structured
* type with its mapping to the class Authors. The following code fragment shows
* how a Map object might be created and given an entry associating
* AUTHORS and Authors.
*
* java.util.Map map = new java.util.HashMap();
* map.put("SCHEMA_NAME.AUTHORS", Class.forName("Authors");
*
*
* The Map object map now contains an entry with the
* fully qualified name of the SQL structured type and the Class
* object for the class Authors. It can be passed to a method
* to tell the driver how to map AUTHORS to Authors.
*
* For a disconnected RowSet object, custom mapping can be done
* only when a Map object is passed to the method or constructor
* that will be doing the custom mapping. The situation is different for
* connected RowSet objects because they maintain a connection
* with the data source. A method that does custom mapping and is called by
* a disconnected RowSet object may use the Map
* object that is associated with the Connection object being
* used. So, in other words, if no map is specified, the connection's type
* map can be used by default.
*/
package javax.sql.rowset.serial;