1/*
2 * Copyright (C) 2006 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
17package android.webkit;
18
19import java.io.Serializable;
20
21/**
22 * This class contains the back/forward list for a WebView.
23 * WebView.copyBackForwardList() will return a copy of this class used to
24 * inspect the entries in the list.
25 */
26public class WebBackForwardList implements Cloneable, Serializable {
27
28    /**
29     *  @hide
30     */
31    public WebBackForwardList() {
32    }
33
34    /**
35     * Return the current history item. This method returns null if the list is
36     * empty.
37     * @return The current history item.
38     */
39    public synchronized WebHistoryItem getCurrentItem() {
40        throw new MustOverrideException();
41    }
42
43    /**
44     * Get the index of the current history item. This index can be used to
45     * directly index into the array list.
46     * @return The current index from 0...n or -1 if the list is empty.
47     */
48    public synchronized int getCurrentIndex() {
49        throw new MustOverrideException();
50    }
51
52    /**
53     * Get the history item at the given index. The index range is from 0...n
54     * where 0 is the first item and n is the last item.
55     * @param index The index to retrieve.
56     */
57    public synchronized WebHistoryItem getItemAtIndex(int index) {
58        throw new MustOverrideException();
59    }
60
61    /**
62     * Get the total size of the back/forward list.
63     * @return The size of the list.
64     */
65    public synchronized int getSize() {
66        throw new MustOverrideException();
67    }
68
69    /**
70     * Clone the entire object to be used in the UI thread by clients of
71     * WebView. This creates a copy that should never be modified by any of the
72     * webkit package classes.
73     */
74    protected synchronized WebBackForwardList clone() {
75        throw new MustOverrideException();
76    }
77
78}
79