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3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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15   * accompanied this code).
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25  
26  package java.sql;
27  
28  /**
29   * The mapping in the Java programming language of an SQL <code>REF</code>
30   * value, which is a reference to an SQL structured type value in the database.
31   * <P>
32   * SQL <code>REF</code> values are stored in a table that contains
33   * instances of a referenceable SQL structured type, and each <code>REF</code>
34   * value is a unique identifier for one instance in that table.
35   * An SQL <code>REF</code> value may be used in place of the
36   * SQL structured type it references, either as a column value in a
37   * table or an attribute value in a structured type.
38   * <P>
39   * Because an SQL <code>REF</code> value is a logical pointer to an
40   * SQL structured type, a <code>Ref</code> object is by default also a logical
41   * pointer. Thus, retrieving an SQL <code>REF</code> value as
42   * a <code>Ref</code> object does not materialize
43   * the attributes of the structured type on the client.
44   * <P>
45   * A <code>Ref</code> object can be stored in the database using the
46   * <code>PreparedStatement.setRef</code> method.
47    * <p>
48   * All methods on the <code>Ref</code> interface must be fully implemented if the
49   * JDBC driver supports the data type.
50   *
51   * @see Struct
52   * @since 1.2
53   */
54  public interface Ref {
55  
56      /**
57       * Retrieves the fully-qualified SQL name of the SQL structured type that
58       * this <code>Ref</code> object references.
59       *
60       * @return the fully-qualified SQL name of the referenced SQL structured type
61       * @exception SQLException if a database access error occurs
62       * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
63       * this method
64       * @since 1.2
65       */
66      String getBaseTypeName() throws SQLException;
67  
68      /**
69       * Retrieves the referenced object and maps it to a Java type
70       * using the given type map.
71       *
72       * @param map a <code>java.util.Map</code> object that contains
73       *        the mapping to use (the fully-qualified name of the SQL
74       *        structured type being referenced and the class object for
75       *        <code>SQLData</code> implementation to which the SQL
76       *        structured type will be mapped)
77       * @return  a Java <code>Object</code> that is the custom mapping for
78       *          the SQL structured type to which this <code>Ref</code>
79       *          object refers
80       * @exception SQLException if a database access error occurs
81       * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
82       * this method
83       * @since 1.4
84       * @see #setObject
85       */
86      Object getObject(java.util.Map<String,Class<?>> map) throws SQLException;
87  
88  
89      /**
90       * Retrieves the SQL structured type instance referenced by
91       * this <code>Ref</code> object.  If the connection's type map has an entry
92       * for the structured type, the instance will be custom mapped to
93       * the Java class indicated in the type map.  Otherwise, the
94       * structured type instance will be mapped to a <code>Struct</code> object.
95       *
96       * @return  a Java <code>Object</code> that is the mapping for
97       *          the SQL structured type to which this <code>Ref</code>
98       *          object refers
99       * @exception SQLException if a database access error occurs
100      * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
101      * this method
102      * @since 1.4
103      * @see #setObject
104      */
105     Object getObject() throws SQLException;
106 
107     /**
108      * Sets the structured type value that this <code>Ref</code>
109      * object references to the given instance of <code>Object</code>.
110      * The driver converts this to an SQL structured type when it
111      * sends it to the database.
112      *
113      * @param value an <code>Object</code> representing the SQL
114      *        structured type instance that this
115      *        <code>Ref</code> object will reference
116      * @exception SQLException if a database access error occurs
117      * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
118      * this method
119      * @since 1.4
120      * @see #getObject()
121      * @see #getObject(Map)
122      * @see PreparedStatement#setObject(int, Object)
123      * @see CallableStatement#setObject(String, Object)
124      */
125     void setObject(Object value) throws SQLException;
126 
127 }