1 /*
 2  * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 4  *
 5  * This code is free software; you can redistribute it and/or modify it
 6  * under the terms of the GNU General Public License version 2 only, as
 7  * published by the Free Software Foundation.  Oracle designates this
 8  * particular file as subject to the "Classpath" exception as provided
 9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package com.sun.javafx.binding;
27 
28 import java.util.Map;
29 import java.util.function.Predicate;
30 
31 import javafx.beans.WeakListener;
32 
33 public class ExpressionHelperBase {
34 
35     protected static int trim(int size, Object[] listeners) {
36         Predicate<Object> p = t -> t instanceof WeakListener &&
37                 ((WeakListener)t).wasGarbageCollected();
38         int index = 0;
39         for (; index < size; index++) {
40             if (p.test(listeners[index])) {
41                 break;
42             }
43         }
44         if (index < size) {
45             for (int src = index + 1; src < size; src++) {
46                 if (!p.test(listeners[src])) {
47                     listeners[index++] = listeners[src];
48                 }
49             }
50             int oldSize = size;
51             size = index;
52             for (; index < oldSize; index++) {
53                 listeners[index] = null;
54             }
55         }
56 
57         return size;
58     }
59 
60     protected static void removeWeakListeners(final Map<?, Integer> listeners) {
61         Predicate<Object> p = t -> t instanceof WeakListener &&
62                 ((WeakListener)t).wasGarbageCollected();
63 
64         listeners.entrySet().removeIf(e -> p.test(e.getKey()));
65     }
66 
67 }