src/org/ibex/jinetd/Watched.java

   1 package org.ibex.jinetd;
   2 import org.ibex.util.*;
   3 import java.io.*;
   4 import java.util.*;
   5
   6 public class Watched extends File {
   7
   8     // Instance //////////////////////////////////////////////////////////////////////////////
   9
  10     private Hashtable cache = new Hashtable();
  11     long lastModifiedAtLastScan = -1;
  12     public final String path;
  13     public final String part;
  14
  15     public Watcher watcher() { return ((Watched)all.get(getParent())).watcher(); }
  16     public Watched slash(String part) { return get(this.path + File.separatorChar + part); }
  17     public void scan() throws IOException {
  18         if (!exists())                                { return; }
  19         if (lastModifiedAtLastScan != lastModified()) { watcher().changed(this); lastModifiedAtLastScan = lastModified(); }
  20         if (!isDirectory())                           { return; }
  21         Vec removals = new Vec();
  22         for(Iterator i = cache.values().iterator(); i.hasNext();) {
  23             Watched w = ((Watched)i.next());
  24             if (w.exists()) w.scan();
  25             else { watcher().changed(w); removals.addElement(w.path.substring(this.path.length() + 1)); }
  26         }
  27         for(int i=0; i<removals.size(); i++) cache.remove(removals.elementAt(i));
  28         String[] kids = list();
  29         if (kids == null) return;
  30         for(int i=0; i<kids.length; i++) {
  31             Watched kid = (Watched)cache.get(kids[i]);
  32             if (kid == null) {
  33                 kid = slash(kids[i]);
  34                 if (kid == null) continue;
  35                 cache.put(kids[i], kid);
  36                 watcher().changed(kid);
  37             } else {
  38                 kid.scan();
  39             }
  40         }
  41     }
  42
  43
  44     // Pooling //////////////////////////////////////////////////////////////////////////////
  45
  46     private static WeakHashMap all = new WeakHashMap();
  47     protected Watched(String path) {
  48         super(path);
  49         this.path = path;
  50         this.part = path.substring(path.lastIndexOf(File.separatorChar) + 1);
  51         all.put(path, this);
  52     }
  53     private static Watched get(String path) {
  54         Watched ret = (Watched)all.get(path);
  55         if (ret == null) ret = new Watched(path);
  56         return ret;
  57     }
  58 }