01: /*
02: * Licensed to the Apache Software Foundation (ASF) under one
03: * or more contributor license agreements. See the NOTICE file
04: * distributed with this work for additional information
05: * regarding copyright ownership. The ASF licenses this file
06: * to you under the Apache License, Version 2.0 (the
07: * "License"); you may not use this file except in compliance
08: * with the License. You may obtain a copy of the License at
09: *
10: * http://www.apache.org/licenses/LICENSE-2.0
11: *
12: * Unless required by applicable law or agreed to in writing,
13: * software distributed under the License is distributed on an
14: * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15: * KIND, either express or implied. See the License for the
16: * specific language governing permissions and limitations
17: * under the License.
18: */
19: package org.apache.openjpa.util;
20:
21: import org.apache.openjpa.kernel.OpenJPAStateManager;
22:
23: /**
24: * Interface implemented by all proxy types to allow setting and nulling
25: * of their owning instance.
26: * All concrete proxy classes should be public and have publc no-args
27: * constructors so that tools that work via reflection on persistent instances
28: * can manipulate them.
29: *
30: * @author Abe White
31: */
32: public interface Proxy {
33:
34: /**
35: * Reset the state of the proxy, and set the owning instance of the
36: * proxy and the name of the field it is assigned to. Set to null to
37: * indicate that the proxy is no longer managed.
38: */
39: public void setOwner(OpenJPAStateManager sm, int field);
40:
41: /**
42: * Return the owning object.
43: */
44: public OpenJPAStateManager getOwner();
45:
46: /**
47: * Return the owning field index.
48: */
49: public int getOwnerField();
50:
51: /**
52: * Return the change tracker for this proxy, or null if none.
53: */
54: public ChangeTracker getChangeTracker();
55:
56: /**
57: * Return an unproxied copy of the given instance. This method is used
58: * by proxy managers to create backup values for use in rollback.
59: */
60: public Object copy(Object orig);
61: }
|