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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.webkit;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;

import com.sun.webkit.event.WCChangeEvent;
import com.sun.webkit.event.WCChangeListener;
import com.sun.webkit.graphics.WCImage;

import static com.sun.webkit.network.URLs.newURL;

public final class BackForwardList {

    public static final class Entry {
        
Native pointer to the HistoryItem object. If 0, the corresponding object has already been destroyed.
/** * Native pointer to the HistoryItem object. * If 0, the corresponding object has already been destroyed. */
private long pitem = 0; // Native pointer to the Page object. private long ppage = 0; private Entry[] children; private URL url; private String title; private Date lastVisitedDate; private WCImage icon; private String target; private boolean isTargetItem; // Only called from the native code. private Entry(long pitem, long ppage) { this.pitem = pitem; this.ppage = ppage; // When the Entry is disposed its fields may be // left uninitialized. As the Entry may still // be referenced from a global history, the fields // should get their initial values here. getURL(); getTitle(); getLastVisitedDate(); getIcon(); getTarget(); isTargetItem(); getChildren(); } // Only called from the native code. private void notifyItemDestroyed() { pitem = 0; } // Called from the native code as well. private void notifyItemChanged() { for (WCChangeListener l : listenerList) { l.stateChanged(new WCChangeEvent(this)); } } public URL getURL() { try { return (pitem == 0 ? url : (url = newURL(bflItemGetURL(pitem)))); } catch (MalformedURLException ex) { return url = null; } } public String getTitle() { return (pitem == 0 ? title : (title = bflItemGetTitle(pitem))); } public WCImage getIcon() { return (pitem == 0 ? icon : (icon = bflItemGetIcon(pitem))); } public String getTarget() { return (pitem == 0 ? target : (target = bflItemGetTarget(pitem))); } public Date getLastVisitedDate() { return lastVisitedDate == null ? null : (Date)lastVisitedDate.clone(); } private void updateLastVisitedDate() { lastVisitedDate = new Date(System.currentTimeMillis()); notifyItemChanged(); } public boolean isTargetItem() { return (pitem == 0 ? isTargetItem : (isTargetItem = bflItemIsTargetItem(pitem))); } public Entry[] getChildren() { return (pitem == 0 ? children : (children = bflItemGetChildren(pitem, ppage))); } @Override public String toString() { return "url=" + getURL() + ",title=" + getTitle() + ",date=" + getLastVisitedDate(); } private final List<WCChangeListener> listenerList = new LinkedList<WCChangeListener>(); public void addChangeListener(WCChangeListener l) { if (l == null) return; listenerList.add(l); } public void removeChangeListener(WCChangeListener l) { if (l == null) return; listenerList.remove(l); } } private final WebPage page; private final List<WCChangeListener> listenerList = new LinkedList<WCChangeListener>(); BackForwardList(WebPage page) { this.page = page; // WebKit doesn't set a page's visiting date. We do it here as workaround. // This way it works for page reload as well. page.addLoadListenerClient(new LoadListenerClient() { @Override public void dispatchLoadEvent(long frame, int state, String url, String contentType, double progress, int errorCode) { if (state == LoadListenerClient.DOCUMENT_AVAILABLE) { Entry entry = getCurrentEntry(); if (entry != null) { entry.updateLastVisitedDate(); } } } @Override public void dispatchResourceLoadEvent(long frame, int state, String url, String contentType, double progress, int errorCode) {} }); } public int size() { return bflSize(page.getPage()); } public int getMaximumSize() { return bflGetMaximumSize(page.getPage()); } public void setMaximumSize(int size) { bflSetMaximumSize(page.getPage(), size); } public int getCurrentIndex() { return bflGetCurrentIndex(page.getPage()); } public boolean isEmpty() { return size() == 0; } public void setEnabled(boolean flag) { bflSetEnabled(page.getPage(), flag); } public boolean isEnabled() { return bflIsEnabled(page.getPage()); } public Entry get(int index) { Entry host = (Entry)bflGet(page.getPage(), index); return host; } public Entry getCurrentEntry() { return get(getCurrentIndex()); } public void clearBackForwardListForDRT() { bflClearBackForwardListForDRT(page.getPage()); } public int indexOf(Entry e) { return bflIndexOf(page.getPage(), e.pitem, false); } public boolean contains(Entry e) { return indexOf(e) >= 0; } public Entry[] toArray() { int size = size(); Entry[] entries = new Entry[size]; for (int i = 0; i < size; i++) { entries[i] = get(i); } return entries; } public void setCurrentIndex(int index) { if (bflSetCurrentIndex(page.getPage(), index) < 0) { throw new IllegalArgumentException("invalid index: " + index); } } private boolean canGoBack(int index) { return index > 0; } public boolean canGoBack() { return canGoBack(getCurrentIndex()); } public boolean goBack() { int index = getCurrentIndex(); if (canGoBack(index)) { setCurrentIndex(index - 1); return true; } return false; } private boolean canGoForward(int index) { return index < (size() - 1); } public boolean canGoForward() { return canGoForward(getCurrentIndex()); } public boolean goForward() { int index = getCurrentIndex(); if (canGoForward(index)) { setCurrentIndex(index + 1); return true; } return false; } public void addChangeListener(WCChangeListener l) { if (l == null) { return; } if (listenerList.isEmpty()) { bflSetHostObject(page.getPage(), this); } listenerList.add(l); } public void removeChangeListener(WCChangeListener l) { if (l == null) { return; } listenerList.remove(l); if (listenerList.isEmpty()) { bflSetHostObject(page.getPage(), null); } } public WCChangeListener[] getChangeListeners() { return listenerList.toArray(new WCChangeListener[0]); } // Only called from the native code. private void notifyChanged() { for (WCChangeListener l : listenerList) { l.stateChanged(new WCChangeEvent(this)); } } native private static String bflItemGetURL(long item); native private static String bflItemGetTitle(long item); native private static WCImage bflItemGetIcon(long item); native private static long bflItemGetLastVisitedDate(long item); native private static boolean bflItemIsTargetItem(long item); native private static Entry[] bflItemGetChildren(long item, long page); native private static String bflItemGetTarget(long item); native private static void bflClearBackForwardListForDRT(long page); native private static int bflSize(long page); native private static int bflGetMaximumSize(long page); native private static void bflSetMaximumSize(long page, int size); native private static int bflGetCurrentIndex(long page); native private static int bflIndexOf(long page, long item, boolean reverse); native private static void bflSetEnabled(long page, boolean flag); native private static boolean bflIsEnabled(long page); native private static Object bflGet(long page, int index); native private static int bflSetCurrentIndex(long page, int index); native private static void bflSetHostObject(long page, Object host); }