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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership. The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License. You may obtain a copy of the License at
9    * 
10   *      http://www.apache.org/licenses/LICENSE-2.0
11   * 
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  package net.jini.core.entry;
19  
20  /**
21   * <p>
22   * This class is the supertype of all entries that can be stored in a Jini
23   * Lookup service.
24   * </p><p>
25   * Each field of an entry must be a public reference (object) type. You cannot
26   * store primitive types in fields of an <code>Entry</code>. An
27   * <code>Entry</code> may have any number of methods or constructors. Each field
28   * is serialized separately, so references between two fields of an entry will
29   * not be reconstituted to be shared references, but instead to separate copies
30   * of the original object.
31   * </p><p>
32   * Implementors notes:
33   * <ul>
34   * <li> New public non-final fields added to an Entry after deployment must be
35   * appended below existing fields to avoid breaking backward compatiblity.
36   * <li> If an Entry implementation is extended by a child class, new public,
37   * non-final fields cannot be added to the parent class, doing so will break
38   * backward compatibility with the child class.
39   * <li> Changing the order of fields in an existing Entry implementation will
40   * break backward compatibility.
41   * <li> Removing fields from an Entry after deployment will break backward
42   * compatiblity.
43   * </ul>
44   * <p>
45   * Recommended practice for backward compatible evolution of Entry's:
46   * </p>
47   * <ol>
48   * <li> Do not change or add public non-final fields to an Entry after
49   * deployment, subclass instead.
50   * <li> Only append public non-final fields to a final Entry class.
51   * <li> Use super-types and interfaces for fields where possible, to allow more
52   * flexibility.
53   * <li> Only use org.apache.river.lookup.util.ConsistentMap or
54   * org.apache.river.lookup.util.ConsistentSet Collection types, or use arrays.
55   * </ol>
56   *
57   * @author Sun Microsystems, Inc.
58   *
59   *
60   * @since 1.0
61   */
62  public interface Entry extends java.io.Serializable {
63  }