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 17 package android.webkit; 18 19 import 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 */ 26 public abstract class WebBackForwardList implements Cloneable, Serializable { 27 /** 28 * Return the current history item. This method returns null if the list is 29 * empty. 30 * @return The current history item. 31 */ 32 public abstract WebHistoryItem getCurrentItem(); 33 34 /** 35 * Get the index of the current history item. This index can be used to 36 * directly index into the array list. 37 * @return The current index from 0...n or -1 if the list is empty. 38 */ 39 public abstract int getCurrentIndex(); 40 41 /** 42 * Get the history item at the given index. The index range is from 0...n 43 * where 0 is the first item and n is the last item. 44 * @param index The index to retrieve. 45 */ 46 public abstract WebHistoryItem getItemAtIndex(int index); 47 48 /** 49 * Get the total size of the back/forward list. 50 * @return The size of the list. 51 */ 52 public abstract int getSize(); 53 54 /** 55 * Clone the entire object to be used in the UI thread by clients of 56 * WebView. This creates a copy that should never be modified by any of the 57 * webkit package classes. 58 */ 59 protected abstract WebBackForwardList clone(); 60 } 61
