Mercurial > hg > digilib-old
view servlet/src/digilib/io/DocuDirCache.java @ 152:f4a5cfe37469
Servlet version 1.16a1
- cleanup of DigilibConfig class
- now uses new Parameter and ParameterMap classes
- new parameter default-quality
author | robcast |
---|---|
date | Wed, 03 Sep 2003 00:54:38 +0200 |
parents | bc8df0133c04 |
children | e743b853efca |
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/* 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; /** * @author casties */ public class DocuDirCache { // HashMap of directories private HashMap map = null; // names of base directories private String[] baseDirNames = null; // number of files in the whole cache (approximate) private long numFiles = 0; // number of cache hits private long hits = 0; // number of cache misses private long misses = 0; /** Constructor with array of base directory names. * * @param bd base directory names */ public DocuDirCache(String[] bd) { baseDirNames = bd; map = new HashMap(); } /** 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(DocuDirectory newdir) { String s = newdir.getDirName(); if (map.containsKey(s)) { System.out.println("Baah, duplicate key in DocuDirectory.put!"); } else { map.put(s, newdir); numFiles += newdir.size(); } } /** Add a directory to the cache and check its parents. * * @param newDir */ public void putDir(DocuDirectory newDir) { put(newDir); String parent = newDir.getParentDirName(); if (parent != null) { // check the parent in the cache DocuDirectory pd = (DocuDirectory)map.get(parent); if (pd == null) { // the parent is unknown pd = new DocuDirectory(parent, this); putDir(pd); } newDir.setParent(pd); } // update dir in the end newDir.readParentMeta(); } /** Returns the DocuFileset with the pathname <code>fn</code> and the * index <code>in</code>. * * If <code>fn</code> is a file then the corresponding Fileset is * returned and the index is ignored. * * @param fn digilib pathname * @param in file index * @return */ public DocuFileset getFileset(String fn, int in) { DocuDirectory dd; // file number is 1-based, vector index is 0-based int n = in - 1; // first, assume fn is a directory and look in the cache dd = (DocuDirectory) map.get(fn); if (dd == null) { // cache miss misses++; // see if it's a directory File f = new File(baseDirNames[0], fn); if (f.isDirectory()) { dd = new DocuDirectory(fn, this); if (dd.isValid()) { // add to the cache putDir(dd); } } else { // maybe it's a file if (f.canRead()) { // get the parent directory string (like we store it in the cache) String d = fn.substring(0, fn.lastIndexOf("/")); // try it in the cache dd = (DocuDirectory) map.get(d); if (dd == null) { // try to read from disk dd = new DocuDirectory(d, this); if (dd.isValid()) { // add to the cache putDir(dd); } else { // invalid path return null; } } else { // then it was not a real cache miss misses--; } // get the file's index n = dd.indexOf(f.getName()); } else { // it's not even a file :-( return null; } } } else { // cache hit hits++; } dd.refresh(); if (dd.isValid()) { try { return dd.get(n); } catch (ArrayIndexOutOfBoundsException e) { } } return null; } /** Returns the DocuDirectory 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 DocuDirectory getDirectory(String fn) { DocuDirectory dd; // first, assume fn is a directory and look in the cache dd = (DocuDirectory) map.get(fn); if (dd == null) { // cache miss misses++; // see if it's a directory File f = new File(baseDirNames[0], fn); if (f.isDirectory()) { dd = new DocuDirectory(fn, this); if (dd.isValid()) { // add to the cache putDir(dd); } } else { // maybe it's a file if (f.canRead()) { // try the parent directory in the cache dd = (DocuDirectory) map.get(f.getParent()); if (dd == null) { // try to read from disk dd = new DocuDirectory(f.getParent(), this); if (dd.isValid()) { // add to the cache putDir(dd); } else { // invalid path return null; } } else { // not a real cache miss then misses--; } } else { // it's not even a file :-( return null; } } } else { // cache hit hits++; } dd.refresh(); if (dd.isValid()) { return dd; } return null; } /** * @return String[] */ public String[] getBaseDirNames() { return baseDirNames; } /** * @return long */ public long getNumFiles() { return numFiles; } /** * Sets the baseDirNames. * @param baseDirNames The baseDirNames to set */ public void setBaseDirNames(String[] baseDirNames) { this.baseDirNames = baseDirNames; } /** * @return long */ public long getHits() { return hits; } /** * @return long */ public long getMisses() { return misses; } }