Delete harder, with a vengeance.

See comment in FileUtil.deleteHarder for rationale.

src/main/java/com/threerings/getdown/classpath/cache/GarbageCollector.java

@@ -20,18 +20,18 @@ public class GarbageCollector
                 File lastAccessedFile = getLastAccessedFile(file);
                 if (!cachedFile.exists() || !lastAccessedFile.exists()) {
                     if (cachedFile.exists()) {
-                        cachedFile.delete();
+                        FileUtil.deleteHarder(cachedFile);
                     } else {
-                        lastAccessedFile.delete();
+                        FileUtil.deleteHarder(lastAccessedFile);
                     }
                 } else if (shouldDelete(lastAccessedFile, retentionPeriodMillis)) {
-                    lastAccessedFile.delete();
-                    cachedFile.delete();
+                    FileUtil.deleteHarder(lastAccessedFile);
+                    FileUtil.deleteHarder(cachedFile);
                 }
 
                 File folder = file.getParentFile();
                 if (folder.list().length == 0) {
-                    folder.delete();
+                    FileUtil.deleteHarder(folder);
                 }
             }
         });

src/main/java/com/threerings/getdown/data/Application.java

@@ -927,7 +927,7 @@ public class Application
             // will have to rediscover that it needs updating and reattempt to update itself
             if (_allowOffline) {
                 log.warning("Failed to update digest files.  Attempting offline operaton.", ex);
-                if (!getLocalPath(VERSION_FILE).delete()) {
+                if (!FileUtil.deleteHarder(getLocalPath(VERSION_FILE))) {
                     log.warning("Deleting version.txt failed.  This probably isn't going to work.");
                 }
             } else {
@@ -1567,7 +1567,7 @@ public class Application
                     signature = StreamUtil.toByteArray(new FileInputStream(signatureFile));
                 } finally {
                     StreamUtil.close(reader);
-                    signatureFile.delete(); // delete the file regardless
+                    FileUtil.deleteHarder(signatureFile); // delete the file regardless
                 }
 
                 byte[] buffer = new byte[8192];
@@ -1605,7 +1605,7 @@ public class Application
                 // if we couldn't find a key that validates our digest, we are the hosed!
                 if (validated == 0) {
                     // delete the temporary digest file as we know it is invalid
-                    target.delete();
+                    FileUtil.deleteHarder(target);
                     throw new IOException("m.corrupt_digest_signature_error");
                 }
             }

src/main/java/com/threerings/getdown/data/Resource.java

@@ -91,7 +91,7 @@ public class Resource implements Comparable<Resource>
                     }
                 }
                 if (tmpJarFile != null) {
-                    tmpJarFile.delete();
+                    FileUtil.deleteHarder(tmpJarFile);
                 }
             }
 
@@ -240,7 +240,7 @@ public class Resource implements Comparable<Resource>
      */
     public void clearMarker ()
     {
-        if (_marker.exists() && !_marker.delete()) {
+        if (_marker.exists() && !FileUtil.deleteHarder(_marker)) {
             log.warning("Failed to erase marker file '" + _marker + "'.");
         }
     }
@@ -291,7 +291,7 @@ public class Resource implements Comparable<Resource>
     public void erase ()
     {
         clearMarker();
-        if (_local.exists() && !_local.delete()) {
+        if (_local.exists() && !FileUtil.deleteHarder(_local)) {
             log.warning("Failed to erase resource '" + _local + "'.");
         }
     }

src/main/java/com/threerings/getdown/launcher/Getdown.java

@@ -722,7 +722,7 @@ public abstract class Getdown extends Thread
                 }
 
                 // clean up the patch file
-                if (!prsrc.getLocal().delete()) {
+                if (!FileUtil.deleteHarder(prsrc.getLocal())) {
                     log.warning("Failed to delete '" + prsrc + "'.");
                     prsrc.getLocal().deleteOnExit();
                 }

src/main/java/com/threerings/getdown/util/FileUtil.java

@@ -45,12 +45,12 @@ public class FileUtil
         // place and then delete the old file
         if (dest.exists()) {
             File temp = new File(dest.getPath() + "_old");
-            if (temp.exists() && !temp.delete()) {
+            if (temp.exists() && !deleteHarder(temp)) {
                 log.warning("Failed to delete old intermediate file " + temp + ".");
                 // the subsequent code will probably fail
             }
             if (dest.renameTo(temp) && source.renameTo(dest)) {
-                if (!temp.delete()) {
+                if (!deleteHarder(temp)) {
                     log.warning("Failed to delete intermediate file " + temp + ".");
                 }
                 return true;
@@ -67,7 +67,7 @@ public class FileUtil
             // close the input stream now so we can delete 'source'
             fin.close();
             fin = null;
-            if (!source.delete()) {
+            if (!deleteHarder(source)) {
                 log.warning("Failed to delete " + source +
                             " after brute force copy to " + dest + ".");
             }
@@ -83,6 +83,18 @@ public class FileUtil
         }
     }
 
+    /**
+     * "Tries harder" to delete {@code file} than just calling {@code delete} on it. Presently this
+     * just means "try a second time if the first time fails." On Windows Vista, sometimes deletes
+     * fail but then succeed if you just try again. Given that delete failure is a rare occurance,
+     * we can implement this hacky workaround without any negative consequences for normal
+     * behavior.
+     */
+    public static boolean deleteHarder (File file) {
+        // if at first you don't succeed... try, try again
+        return file.delete() || file.delete();
+    }
+
     /**
      * Reads the contents of the supplied input stream into a list of lines. Closes the reader on
      * successful or failed completion.

src/main/java/com/threerings/getdown/util/LaunchUtil.java

@@ -144,13 +144,13 @@ public class LaunchUtil
 
         // clear out any old getdown
         if (oldgd.exists()) {
-            oldgd.delete();
+            FileUtil.deleteHarder(oldgd);
         }
 
         // now try updating using renames
         if (!curgd.exists() || curgd.renameTo(oldgd)) {
             if (newgd.renameTo(curgd)) {
-                oldgd.delete(); // yay!
+                FileUtil.deleteHarder(oldgd); // yay!
                 try {
                     // copy the moved file back to getdown-dop-new.jar so that we don't end up
                     // downloading another copy next time