[RFC] Fix IndexOutOfBoundException because of corrupted entry in recently_used file

[Thomas Meyer]

# HG changeset patch
# User Thomas Meyer <thomas at m3y3r.de>
# Date 1332937976 -7200
# Node ID f6540088f06f2d9962e1c5b7858c4212f045759e
# Parent  093896b370d3ed3f1fc3527084133b8e388bf0ae
Fix IndexOutOfBoundException because of corrupt "recently_used" index file of cached files. Better solution would be to do this validation in CacheLRUWrapper.load()

diff -r 093896b370d3 -r f6540088f06f netx/net/sourceforge/jnlp/cache/CacheUtil.java
--- a/netx/net/sourceforge/jnlp/cache/CacheUtil.java	Wed Mar 28 12:08:10 2012 +0200
+++ b/netx/net/sourceforge/jnlp/cache/CacheUtil.java	Wed Mar 28 14:32:56 2012 +0200
@@ -354,17 +354,22 @@
 
                 }
             } while (entries == null);
+
             // Start searching from the most recent to least recent.
             for (Entry<String, String> e : entries) {
                 final String key = e.getKey();
-                final String path = e.getValue();
+                String path = e.getValue();
 
                 if (path != null) {
-                    if (pathToURLPath(path).equals(urlPath.getPath())) { // Match found.
-                        cacheFile = new File(path);
-                        lruHandler.updateEntry(key);
-                        break; // Stop searching since we got newest one already.
-                    }
+                    path=pathToURLPath(path);
+                    if(path == null)
+                        lruHandler.removeEntry(key);
+                    else
+                        if (path.equals(urlPath.getPath())) { // Match found.
+                            cacheFile = new File(path);
+                            lruHandler.updateEntry(key);
+                            break; // Stop searching since we got newest one already.
+                        }
                 }
             }
             return cacheFile;
@@ -377,6 +382,13 @@
     private static String pathToURLPath(String path) {
         int len = cacheDir.length();
         int index = path.indexOf(File.separatorChar, len + 1);
+
+        /*
+         * somehow the lru entries got corrupt. ignore this entry and
+         * don't fail with an IndexOutOfBoundsException
+         */
+        if(index < 0)
+            return null;
         return path.substring(index);
     }