J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1999-2004 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package sun.java2d.loops; |
| 27 | |
| 28 | public final class RenderCache { |
| 29 | final class Entry { |
| 30 | private SurfaceType src; |
| 31 | private CompositeType comp; |
| 32 | private SurfaceType dst; |
| 33 | private Object value; |
| 34 | |
| 35 | public Entry(SurfaceType src, |
| 36 | CompositeType comp, |
| 37 | SurfaceType dst, |
| 38 | Object value) |
| 39 | { |
| 40 | this.src = src; |
| 41 | this.comp = comp; |
| 42 | this.dst = dst; |
| 43 | this.value = value; |
| 44 | } |
| 45 | |
| 46 | public boolean matches(SurfaceType src, |
| 47 | CompositeType comp, |
| 48 | SurfaceType dst) |
| 49 | { |
| 50 | // bug 4725045: using equals() causes different SurfaceType |
| 51 | // objects with the same strings to match in the cache, which is |
| 52 | // not the behavior we want. Constrain the match to succeed only |
| 53 | // on object matches instead. |
| 54 | return ((this.src == src) && |
| 55 | (this.comp == comp) && |
| 56 | (this.dst == dst)); |
| 57 | } |
| 58 | |
| 59 | public Object getValue() { |
| 60 | return value; |
| 61 | } |
| 62 | } |
| 63 | |
| 64 | private Entry entries[]; |
| 65 | |
| 66 | public RenderCache(int size) { |
| 67 | entries = new Entry[size]; |
| 68 | } |
| 69 | |
| 70 | public synchronized Object get(SurfaceType src, |
| 71 | CompositeType comp, |
| 72 | SurfaceType dst) |
| 73 | { |
| 74 | int max = entries.length - 1; |
| 75 | for (int i = max; i >= 0; i--) { |
| 76 | Entry e = entries[i]; |
| 77 | if (e == null) { |
| 78 | break; |
| 79 | } |
| 80 | if (e.matches(src, comp, dst)) { |
| 81 | if (i < max - 4) { |
| 82 | System.arraycopy(entries, i+1, entries, i, max - i); |
| 83 | entries[max] = e; |
| 84 | } |
| 85 | return e.getValue(); |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | return null; |
| 90 | } |
| 91 | |
| 92 | public synchronized void put(SurfaceType src, |
| 93 | CompositeType comp, |
| 94 | SurfaceType dst, |
| 95 | Object value) |
| 96 | { |
| 97 | Entry e = new Entry(src, comp, dst, value); |
| 98 | |
| 99 | int num = entries.length; |
| 100 | System.arraycopy(entries, 1, entries, 0, num - 1); |
| 101 | entries[num - 1] = e; |
| 102 | } |
| 103 | } |