1 /*
2 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
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
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
36 * these wrapped resources
37 * represented by their proxy, to permit direct access to the resource delegates.
38 *
39 * @since 1.6
40 */
41
42 public interface Wrapper {
43
44 /**
45 * Returns an object that implements the given interface to allow access to
46 * non-standard methods, or standard methods not exposed by the proxy.
47 *
48 * If the receiver implements the interface then the result is the receiver
49 * or a proxy for the receiver. If the receiver is a wrapper
50 * and the wrapped object implements the interface then the result is the
51 * wrapped object or a proxy for the wrapped object. Otherwise return the
52 * the result of calling <code>unwrap</code> recursively on the wrapped object
53 * or a proxy for that result. If the receiver is not a
54 * wrapper and does not implement the interface, then an <code>SQLException</code> is thrown.
55 *
56 * @param iface A Class defining an interface that the result must implement.
57 * @return an object that implements the interface. May be a proxy for the actual implementing object.
58 * @throws java.sql.SQLException If no object found that implements the interface
59 * @since 1.6
60 */
61 <T> T unwrap(java.lang.Class<T> iface) throws java.sql.SQLException;
62
63 /**
64 * Returns true if this either implements the interface argument or is directly or indirectly a wrapper
65 * for an object that does. Returns false otherwise. If this implements the interface then return true,
66 * else if this is a wrapper then return the result of recursively calling <code>isWrapperFor</code> on the wrapped
67 * object. If this does not implement the interface and is not a wrapper, return false.
68 * This method should be implemented as a low-cost operation compared to <code>unwrap</code> so that
69 * callers can use this method to avoid expensive <code>unwrap</code> calls that may fail. If this method
70 * returns true then calling <code>unwrap</code> with the same argument should succeed.
71 *
72 * @param iface a Class defining an interface.
73 * @return true if this implements the interface or directly or indirectly wraps an object that does.
74 * @throws java.sql.SQLException if an error occurs while determining whether this is a wrapper
75 * for an object with the given interface.
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1 /*
2 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
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
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
36 * these wrapped resources
37 * represented by their proxy, to permit direct access to the resource delegates.
38 *
39 * @since 1.6
40 */
41
42 public interface Wrapper {
43
44 /**
45 * Returns an object that implements the given interface to allow access to
46 * non-standard methods, or standard methods not exposed by the proxy.
47 *
48 * If the receiver implements the interface then the result is the receiver
49 * or a proxy for the receiver. If the receiver is a wrapper
50 * and the wrapped object implements the interface then the result is the
51 * wrapped object or a proxy for the wrapped object. Otherwise return the
52 * the result of calling <code>unwrap</code> recursively on the wrapped object
53 * or a proxy for that result. If the receiver is not a
54 * wrapper and does not implement the interface, then an <code>SQLException</code> is thrown.
55 *
56 * @param <T> the type of the class modeled by this Class object
57 * @param iface A Class defining an interface that the result must implement.
58 * @return an object that implements the interface. May be a proxy for the actual implementing object.
59 * @throws java.sql.SQLException If no object found that implements the interface
60 * @since 1.6
61 */
62 <T> T unwrap(java.lang.Class<T> iface) throws java.sql.SQLException;
63
64 /**
65 * Returns true if this either implements the interface argument or is directly or indirectly a wrapper
66 * for an object that does. Returns false otherwise. If this implements the interface then return true,
67 * else if this is a wrapper then return the result of recursively calling <code>isWrapperFor</code> on the wrapped
68 * object. If this does not implement the interface and is not a wrapper, return false.
69 * This method should be implemented as a low-cost operation compared to <code>unwrap</code> so that
70 * callers can use this method to avoid expensive <code>unwrap</code> calls that may fail. If this method
71 * returns true then calling <code>unwrap</code> with the same argument should succeed.
72 *
73 * @param iface a Class defining an interface.
74 * @return true if this implements the interface or directly or indirectly wraps an object that does.
75 * @throws java.sql.SQLException if an error occurs while determining whether this is a wrapper
76 * for an object with the given interface.
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