/* * Copyright © 2010 Anthony Towns * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program 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 for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ package org.altusmetrum.altosuilib_2; import javax.swing.*; import javax.imageio.ImageIO; import java.awt.image.*; import java.awt.*; import java.io.*; import java.net.*; public class AltosUIMapCache { static final int success = 0; static final int loading = 1; static final int failed = 2; static final int bad_request = 3; static final int forbidden = 4; static final int min_cache_size = 9; static final int max_cache_size = 24; private Object fetch_lock = new Object(); private Object cache_lock = new Object(); int cache_size = min_cache_size; AltosUIMapImage[] images = new AltosUIMapImage[cache_size]; long used; public void set_cache_size(int new_size) { if (new_size < min_cache_size) new_size = min_cache_size; if (new_size > max_cache_size) new_size = max_cache_size; if (new_size == cache_size) return; synchronized(cache_lock) { AltosUIMapImage[] new_images = new AltosUIMapImage[new_size]; for (int i = 0; i < cache_size; i++) { if (i < new_size) new_images[i] = images[i]; else if (images[i] != null) images[i].flush(); } images = new_images; cache_size = new_size; } } public Image get(AltosUIMapTile tile, AltosUIMapStore store, int width, int height) { int oldest = -1; long age = used; synchronized(cache_lock) { AltosUIMapImage image = null; for (int i = 0; i < cache_size; i++) { image = images[i]; if (image == null) { oldest = i; break; } if (store.equals(image.store)) { image.used = used++; return image.image; } if (image.used < age) { oldest = i; age = image.used; } } try { image = new AltosUIMapImage(tile, store); image.used = used++; if (images[oldest] != null) images[oldest].flush(); images[oldest] = image; if (image.image == null) tile.set_status(loading); else tile.set_status(success); return image.image; } catch (IOException e) { tile.set_status(failed); return null; } } } public AltosUIMapCache() { } }