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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * accompanied this code).

 *

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 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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package java.sql;

/**

 * The mapping in the Java programming language of an SQL {@code REF}

 * value, which is a reference to an SQL structured type value in the database.

 * <P>

 * SQL {@code REF} values are stored in a table that contains

 * instances of a referenceable SQL structured type, and each {@code REF}

 * value is a unique identifier for one instance in that table.

 * An SQL {@code 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.

 * <P>

 * Because an SQL {@code REF} value is a logical pointer to an

 * SQL structured type, a {@code Ref} object is by default also a logical

 * pointer. Thus, retrieving an SQL {@code REF} value as

 * a {@code Ref} object does not materialize

 * the attributes of the structured type on the client.

 * <P>

 * A {@code Ref} object can be stored in the database using the

 * {@code PreparedStatement.setRef} method.

  * <p>

 * All methods on the {@code Ref} interface must be fully implemented if the

 * JDBC driver supports the data type.

 *

 * @see Struct

 * @since 1.2

 */

public interface Ref {

    /**

     * Retrieves the fully-qualified SQL name of the SQL structured type that

     * this {@code Ref} object references.

     *

     * @return the fully-qualified SQL name of the referenced SQL structured type

     * @throws SQLException if a database access error occurs

     * @throws SQLFeatureNotSupportedException if the JDBC driver does not support

     * this method

     * @since 1.2

     */

    String getBaseTypeName() throws SQLException;

    /**

     * Retrieves the referenced object and maps it to a Java type

     * using the given type map.

     *

     * @param map a {@code 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

     *        {@code SQLData} implementation to which the SQL

     *        structured type will be mapped)

     * @return  a Java {@code Object} that is the custom mapping for

     *          the SQL structured type to which this {@code Ref}

     *          object refers

     * @throws SQLException if a database access error occurs

     * @throws SQLFeatureNotSupportedException if the JDBC driver does not support

     * this method

     * @since 1.4

     * @see #setObject

     */

    Object getObject(java.util.Map<String,Class<?>> map) throws SQLException;

    /**

     * Retrieves the SQL structured type instance referenced by

     * this {@code 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 {@code Struct} object.

     *

     * @return  a Java {@code Object} that is the mapping for

     *          the SQL structured type to which this {@code Ref}

     *          object refers

     * @throws SQLException if a database access error occurs

     * @throws SQLFeatureNotSupportedException if the JDBC driver does not support

     * this method

     * @since 1.4

     * @see #setObject

     */

    Object getObject() throws SQLException;

    /**

     * Sets the structured type value that this {@code Ref}

     * object references to the given instance of {@code Object}.

     * The driver converts this to an SQL structured type when it

     * sends it to the database.

     *

     * @param value an {@code Object} representing the SQL

     *        structured type instance that this

     *        {@code Ref} object will reference

     * @throws SQLException if a database access error occurs

     * @throws SQLFeatureNotSupportedException if the JDBC driver does not support

     * this method

     * @since 1.4

     * @see #getObject()

     * @see #getObject(Map)

     * @see PreparedStatement#setObject(int, Object)

     * @see CallableStatement#setObject(String, Object)

     */

    void setObject(Object value) throws SQLException;

}