1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.betwixt.strategy;
18
19 /**
20 * <p>Pluggable strategy determines whether introspection or bind time
21 * typing should be used when finding mappings.
22 * The type of a property is determined at introspection time but
23 * the actual type of the instance can differ at bind time (when the
24 * xml is actually being processed). This strategy is used to set
25 * (at a per-element level) whether the bind or introspection
26 * time type should be used to calculate the mapping to be used.
27 * </p>
28 * <p>
29 * <strong>Note:</strong> this strategy is intentionally course.
30 * Typically, the best approach is to use a custom strategy to set
31 * coursely grained rules (for example: all implemetations of 'IAnimal'
32 * use bind time type mapping) and then dot betwixt files to provide
33 * refinements.
34 * </p>
35 * @since 0.7
36 * @author <a href='http://commons.apache.org'>Apache Commons Team</a>,
37 * <a href='http://www.apache.org'>Apache Software Foundation</a>
38 */
39 public abstract class MappingDerivationStrategy {
40
41 /**
42 * Implementation that always uses bind time type mapping
43 */
44 public static final MappingDerivationStrategy USE_BIND_TIME_TYPE
45 = new MappingDerivationStrategy() {
46 public boolean useBindTimeTypeForMapping(Class propertyType, Class singluarPropertyType) {
47 return true;
48 }
49 };
50
51 /**
52 * Implementation that always uses introspection time type mapping
53 */
54 public static final MappingDerivationStrategy USE_INTROSPECTION_TIME_TYPE
55 = new MappingDerivationStrategy() {
56 public boolean useBindTimeTypeForMapping(Class propertyType, Class singluarPropertyType) {
57 return false;
58 }
59 };
60
61 /**
62 * The default Betwixt strategy.
63 */
64 public static final MappingDerivationStrategy DEFAULT = USE_BIND_TIME_TYPE;
65
66 /**
67 * Should bind time type be used for all elements of the given property type?
68 * @param propertyType <code>Class</code> typing the property, not null
69 * @param singluarPropertyType <code>Class</code> composing the collective
70 * or null if the property is not collective
71 * @return true if bind time type should be used for the mapping
72 */
73 public abstract boolean useBindTimeTypeForMapping(Class propertyType, Class singluarPropertyType);
74 }