--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/servlet/src/digilib/io/DocuDirCache.java	Wed Nov 17 18:17:34 2004 +0100
@@ -0,0 +1,240 @@
+/*
+ * DocuDirCache.java
+ * 
+ * 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 03.03.2003
+ */
+
+package digilib.io;
+
+import java.io.File;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.log4j.Logger;
+
+/**
+ * Cache of digilib directories.
+ * 
+ * @author casties
+ */
+public class DocuDirCache {
+
+	/** general logger for this class */
+	protected static Logger logger = Logger.getLogger(DocuDirCache.class);
+
+	/** Map of directories */
+	Map map = null;
+
+	/** number of files in the whole cache (approximate) */
+	long numFiles = 0;
+
+	/** number of cache hits */
+	long hits = 0;
+
+	/** number of cache misses */
+	long misses = 0;
+
+	/** the root directory element */
+	public DigiDirectory rootDir = null;
+
+	/**
+	 * Default constructor.
+	 */
+	public DocuDirCache() {
+		map = new HashMap();
+		// add root directory
+		rootDir = new DigiDirectory(FileOps.getBaseDirs()[0], "", null);
+		map.put("", rootDir);
+	}
+
+	/**
+	 * The number of directories in the cache.
+	 * 
+	 * @return
+	 */
+	public int size() {
+		return (map != null) ? map.size() : 0;
+	}
+
+	/**
+	 * Add a DocuDirectory to the cache.
+	 * 
+	 * @param newdir
+	 */
+	public void put(DigiDirectory newdir) {
+		String s = newdir.getDLPath();
+		Object oldkey = map.put(s, newdir);
+		if (oldkey != null) {
+			logger.warn("Duplicate key in DocuDirCache.put -- overwritten!");
+		}
+		numFiles += newdir.getSize();
+	}
+
+	/**
+	 * Add a directory to the cache and check its parents.
+	 * 
+	 * @param newDir
+	 */
+	public synchronized void putDir(DigiDirectory newDir) {
+		put(newDir);
+	}
+
+	/**
+	 * Returns a DigiDirectory from the cache.
+	 * 
+	 * @param path
+	 * @return
+	 */
+	public DigiDirectory get(String path) {
+		return (DigiDirectory) map.get(path);
+	}
+
+	/**
+	 * Returns the DigiDirectory indicated by the pathname <code>fn</code>.
+	 * 
+	 * If <code>fn</code> is a file then its parent directory is returned.
+	 * 
+	 * @param fn
+	 *            digilib pathname
+	 * @return
+	 */
+	public DigiDirectory getDirectory(String pn) {
+		/*
+		 * first, assume pn is a directory and look in the cache
+		 */
+		DigiDirectory dd = (DigiDirectory) map.get(pn);
+		if (dd != null) {
+			// cache hit
+			hits++;
+			return dd;
+		} else {
+			/*
+			 * maybe it's a file? try the parent directory
+			 */
+			String dn = FileOps.dlParent(pn);
+			// try it in the cache
+			dd = (DigiDirectory) map.get(dn);
+			if (dd != null) {
+				// cache hit
+				hits++;
+				return dd;
+			} else {
+				// cache miss
+				misses++;
+				/*
+				 * try to read from disk
+				 */
+				File f = FileOps.getRealFile(pn);
+				/*
+				 * is it a directory?
+				 */
+				if (f.isDirectory()) {
+					dd = new DigiDirectory(f, pn, null);
+					// add to the cache
+					putDir(dd);
+					return dd;
+				} else {
+					/*
+					 * then maybe a file? try the parent as a directory
+					 */
+					File d = FileOps.getRealFile(dn);
+					if (d.isDirectory()) {
+						dd = new DigiDirectory(d, dn, null);
+						// add to the cache
+						putDir(dd);
+						return dd;
+					}
+				}
+			}
+		}
+		/*
+		 * otherwise it's crap
+		 */
+		return null;
+	}
+
+	/**
+	 * Returns the DigiDirent with the pathname <code>fn</code> and the index
+	 * <code>in</code> and the class <code>fc</code>.
+	 * 
+	 * If <code>fn</code> is a file then the corresponding DocuDirent is
+	 * returned and the index is ignored.
+	 * 
+	 * @param pn
+	 *            digilib pathname
+	 * @param in
+	 *            file index
+	 * @param fc
+	 *            file class
+	 * @return
+	 */
+	public DigiDirent getFile(String pn, int in, int fc) {
+		// file number is 1-based, vector index is 0-based
+		int n = in - 1;
+		// get the (parent) directory
+		DigiDirectory dd = getDirectory(pn);
+		if (dd != null) {
+			// get the directory's name
+			String dn = dd.getDLPath();
+			if (dn.equals(pn)) {
+				// return the file at the index
+				return dd.get(n, fc);
+			} else {
+				// then the last part must be the filename
+				String fn = FileOps.dlName(pn);
+				return dd.get(fn);
+			}
+		}
+		return null;
+	}
+
+	/**
+	 * @return long
+	 */
+	public long getNumFiles() {
+		return numFiles;
+	}
+
+	/**
+	 * @return long
+	 */
+	public long getHits() {
+		return hits;
+	}
+
+	/**
+	 * @return long
+	 */
+	public long getMisses() {
+		return misses;
+	}
+
+	/**
+	 * @return Returns the rootDir.
+	 */
+	public DigiDirectory getRootDir() {
+		return rootDir;
+	}
+	/**
+	 * @param rootDir The rootDir to set.
+	 */
+	public void setRootDir(DigiDirectory rootDir) {
+		this.rootDir = rootDir;
+	}
+}