1 /*
2  * Copyright (C) 2009 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package signature.compare.model;
18 
19 /**
20  * {@code IDelta} is the common base interface for all delta model elements. It
21  * describes a delta from a "from" element to a "to" element.
22  *
23  * @param <T>
24  *            the type of the compared elements
25  */
26 public interface IDelta<T> {
27 
28     /**
29      * Returns the type of this delta.
30      *
31      * @return the type of this delta
32      */
getType()33     DeltaType getType();
34 
35     /**
36      * Returns the "from" element. Is null if type is {@link DeltaType#ADDED}
37      *
38      * @return the "from" element
39      */
getFrom()40     T getFrom();
41 
42     /**
43      * Returns the "to" element. Is null if type is {@link DeltaType#REMOVED}
44      *
45      * @return the "to" element
46      */
getTo()47     T getTo();
48 }
49