1 files changed, 112 insertions, 0 deletions
diff --git a/altosuilib/AltosUIMapCache.java b/altosuilib/AltosUIMapCache.java
new file mode 100644
index 00000000..e849da79
--- /dev/null
+++ b/altosuilib/AltosUIMapCache.java
@@ -0,0 +1,112 @@
+/*
+ * Copyright © 2010 Anthony Towns <aj@erisian.com.au>
+ *
+ * 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 private Object fetch_lock = new Object();
+
+	static final int		min_cache_size = 9;
+	static final int		max_cache_size = 24;
+
+	static int			cache_size = min_cache_size;
+
+	static AltosUIMapImage[]	images = new AltosUIMapImage[cache_size];
+
+	static Object cache_lock = new Object();
+
+	public  static 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;
+		}
+	}
+
+	static long			used;
+
+	public static 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;
+			}
+		}
+	}
+}