--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/servlet/src/digilib/io/FileOps.java	Thu Jan 17 15:25:46 2002 +0100
@@ -0,0 +1,188 @@
+/*  FileOps -- Utility class for file operations
+
+  Digital Image Library servlet components
+
+  Copyright (C) 2001, 2002 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
+
+*/
+
+package digilib.io;
+
+import java.io.*;
+import java.util.*;
+
+import digilib.*;
+
+
+public class FileOps {
+
+  private Utils util = null;
+  public static String[] fileTypes = {
+            "jpg", "image/jpeg",
+            "jpeg", "image/jpeg",
+            "png", "image/png",
+            "gif", "image/gif",
+            "tif", "image/tiff",
+            "tiff", "image/tiff"};
+
+  public FileOps() {
+    util = new Utils();
+  }
+
+  public FileOps(Utils u) {
+    util = u;
+  }
+
+  public void setUtils(Utils u) {
+    util = u;
+  }
+
+
+  /**
+   *  get the mime type for a file format (by extension)
+   */
+  public static String mimeForFile(File f) {
+    String fn = f.getName();
+    for (int i = 0; i < fileTypes.length; i += 2) {
+      if (fn.toLowerCase().endsWith(fileTypes[i])) {
+        return fileTypes[i+1];
+      }
+    }
+    return null;
+  }
+
+  /**
+   *  get a filehandle for a file or directory name
+   *    returns File number n if fn is directory (starts with 1)
+   */
+  public File getFile(String fn, int n) throws FileOpException {
+    util.dprintln(4, "getFile ("+fn+", "+n+")");
+
+    File f = new File(fn);
+    // if fn is a file name then return file
+    if (f.isFile()) {
+      return f;
+    }
+    // if fn is a directory name then open directory
+    if (f.isDirectory()) {
+      File[] fl = f.listFiles(new ImgFileFilter());
+      Arrays.sort(fl);
+      if ((n > 0) && (n <= fl.length)) {
+         return fl[n - 1];
+      }
+    }
+    throw new FileOpException("Unable to find file: "+fn);
+  }
+
+  /**
+   *  get the number of files in a directory
+   *    (almost the same as getFile)
+   *  returns 0 in case of problems
+   */
+  public int getNumFiles(String fn) throws FileOpException {
+    util.dprintln(4, "getNumFiles ("+fn+")");
+
+    File f = new File(fn);
+    // if fn is a file name then return 1
+    if (f.isFile()) {
+      return 1;
+    }
+    // if fn is a directory name then return the number of files
+    if (f.isDirectory()) {
+      return f.listFiles(new ImgFileFilter()).length;
+    }
+    // then fn must be something strange...
+    return 0;
+  }
+
+
+  /**
+   *  get a filehandle for a file or directory name out of a list
+   *    dirs is a list of base directories, fn is the appended file/dirname
+   *    searches dirs until fn exists (backwards if fwd is false)
+   *    returns File number n if fn is directory (starts with 1)
+   */
+  public File getFileVariant(String[] dirs, String fn, int n, boolean fwd) throws FileOpException {
+    util.dprintln(4, "getVariantFile ("+dirs+", "+fn+", "+n+")");
+
+    File f = null;
+    int start = 0;
+    int inc = 1;
+    int end = dirs.length;
+    if (fwd == false) {
+      start = dirs.length - 1;
+      inc = -1;
+      end = 0;
+    }
+
+    for (int i = start; i != end; i += inc) {
+      try {
+        f = getFile(dirs[i]+fn, n);
+      } catch (FileOpException e) {
+        f = null;
+      }
+      if (f != null) {
+        return f;
+      }
+    }
+    throw new FileOpException("Unable to find file: "+fn);
+  }
+
+  /**
+   *  get the number of files in a directory
+   *    (almost the same as getFileVariant)
+   *  returns 0 in case of problems
+   */
+  public int getNumFilesVariant(String[] dirs, String fn, boolean fwd) throws FileOpException {
+    util.dprintln(4, "getNumFilesVariant ("+dirs+", "+fn+")");
+
+    int nf = 0;
+    int start = 0;
+    int inc = 1;
+    int end = dirs.length;
+    if (fwd == false) {
+      start = dirs.length - 1;
+      inc = -1;
+      end = 0;
+    }
+
+    for (int i = start; i != end; i += inc) {
+      try {
+        nf = getNumFiles(dirs[i]+fn);
+      } catch (FileOpException e) {
+        nf = 0;
+      }
+      if (nf > 0) {
+        return nf;
+      }
+    }
+    return 0;
+  }
+
+  /**
+   *  FileFilter for image types (helper class for getFile)
+   */
+  private class ImgFileFilter implements FileFilter {
+
+    public boolean accept(File f) {
+      if (f.isFile()) {
+        return (mimeForFile(f) != null);
+      } else {
+        return false;
+      }
+    }
+  }
+
+}