--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/common/src/main/java/digilib/io/AliasingDocuDirCache.java	Tue Apr 26 20:24:31 2011 +0200
@@ -0,0 +1,98 @@
+/*
+ * AliasingDocuDirCache -- DocuDirCache using alias entries from config file
+ * 
+ * Digital Image Library servlet components
+ * 
+ * Copyright (C) 2003 Robert Casties (robcast@mail.berlios.de)
+ * 
+ * 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; either version 2 of the License, or (at your option)
+ * any later version.
+ * 
+ * Please read license.txt for the full details. A copy of the GPL may be found
+ * at http://www.gnu.org/copyleft/lgpl.html
+ * 
+ * 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
+ * 
+ * Created on 04.11.2003
+ */
+
+package digilib.io;
+
+import java.io.File;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import digilib.io.FileOps.FileClass;
+import digilib.servlet.DigilibConfiguration;
+import digilib.util.XMLListLoader;
+
+/**
+ * @author casties
+ *  
+ */
+public class AliasingDocuDirCache extends DocuDirCache {
+
+	/**
+	 * @param baseDirs
+	 * @param fcs
+	 * @param confFileName
+	 * @throws FileOpException
+	 */
+	public AliasingDocuDirCache(String[] baseDirs, FileClass[] fcs,
+			File confFile, DigilibConfiguration dlConfig)
+			throws FileOpException {
+		// create standard DocuDirCache
+		super(baseDirs, fcs, dlConfig);
+		Map<String,String> pathMap = null;
+		// read alias config file
+		try {
+			// load into pathMap
+			XMLListLoader mapLoader = new XMLListLoader("digilib-aliases",
+					"mapping", "link", "dir");
+			pathMap = mapLoader.loadURL(confFile.toURL().toString());
+		} catch (Exception e) {
+			throw new FileOpException("ERROR loading mapping file: " + e);
+		}
+		if (pathMap == null) {
+			throw new FileOpException("ERROR: unable to load mapping file!");
+		}
+
+		/*
+		 * load map entries into cache
+		 */
+
+		for (Entry<String, String> linkdir: pathMap.entrySet()) {
+			if (linkdir.getValue() == null) {
+				logger.error("Key mismatch in mapping file!");
+				break;	
+			}
+			DocuDirectory destDir = new DocuDirectory(linkdir.getValue(), this);
+			if (destDir.isValid()) {
+				logger.debug("Aliasing dir: " + linkdir.getKey());
+				// add the alias name
+				putName(FileOps.normalName(linkdir.getKey()), destDir);
+				// add the real dir
+				putDir(destDir);
+			}
+		}
+	}
+
+	/**
+	 * Adds a DocuDirectory under another name to the cache.
+	 * 
+	 * @param name
+	 * @param newdir
+	 */
+    public void putName(String name, DocuDirectory newdir) {
+        if (map.containsKey(name)) {
+            logger.warn("Duplicate key in AliasingDocuDirCache.put -- ignored!");
+        } else {
+            map.put(name, newdir);
+        }
+    }
+
+}