diff --git a/core/src/main/java/com/threerings/getdown/data/Resource.java b/core/src/main/java/com/threerings/getdown/data/Resource.java
index e8f8f1d..78ca844 100644
--- a/core/src/main/java/com/threerings/getdown/data/Resource.java
+++ b/core/src/main/java/com/threerings/getdown/data/Resource.java
@@ -62,17 +62,18 @@ public class Resource implements Comparable<Resource>
         byte[] buffer = new byte[DIGEST_BUFFER_SIZE];
         int read;
 
-        boolean isJar = isJar(target.getPath());
-        boolean isPacked200Jar = isPacked200Jar(target.getPath());
+        boolean isJar = isJar(target);
+        boolean isPacked200Jar = isPacked200Jar(target);
 
         // if this is a jar, we need to compute the digest in a "timestamp and file order" agnostic
         // manner to properly correlate jardiff patched jars with their unpatched originals
         if (isJar || isPacked200Jar){
+            File tmpJarFile = null;
             ZipFile jar = null;
             try {
                 // if this is a compressed jar file, uncompress it to compute the jar file digest
                 if (isPacked200Jar){
-                    File tmpJarFile = new File(target.getPath() + ".tmp");
+                    tmpJarFile = new File(target.getPath() + ".tmp");
                     tmpJarFile.deleteOnExit();
                     jar = FileUtil.unpackPacked200Jar(target, tmpJarFile);
                 } else{
@@ -109,6 +110,9 @@ public class Resource implements Comparable<Resource>
                         log.warning("Error closing jar", "path", target, "jar", jar, "error", ioe);
                     }
                 }
+                if (tmpJarFile != null) {
+                    FileUtil.deleteHarder(tmpJarFile);
+                }
             }
 
         } else {
@@ -133,12 +137,11 @@ public class Resource implements Comparable<Resource>
         _remote = remote;
         _local = local;
         _localNew = new File(local.toString() + "_new");
-        String lpath = _local.getPath();
-        _marker = new File(lpath + "v");
+        _marker = new File(_local.getPath() + "v");
 
         _attrs = attrs;
-        _isJar = isJar(lpath);
-        _isPacked200Jar = isPacked200Jar(lpath);
+        _isJar = isJar(local);
+        _isPacked200Jar = isPacked200Jar(local);
         boolean unpack = attrs.contains(Attr.UNPACK);
         if (unpack && _isJar) {
             _unpacked = _local.getParentFile();
@@ -339,7 +342,11 @@ public class Resource implements Comparable<Resource>
 
     @Override public boolean equals (Object other)
     {
-        return other instanceof Resource && _path.equals(((Resource) other)._path);
+        if (other instanceof Resource) {
+            return _path.equals(((Resource)other)._path);
+        } else {
+            return false;
+        }
     }
 
     @Override public int hashCode ()
@@ -360,13 +367,16 @@ public class Resource implements Comparable<Resource>
         }
     }
 
-    protected static boolean isJar (String path)
+    protected static boolean isJar (File file)
     {
-        return path.endsWith(".jar") || path.endsWith(".jar_new") || path.endsWith(".zip");
+        String path = file.getName();
+        return path.endsWith(".jar") || path.endsWith(".jar_new") ||
+            path.endsWith(".zip") || path.endsWith(".zip_new");
     }
 
-    protected static boolean isPacked200Jar (String path)
+    protected static boolean isPacked200Jar (File file)
     {
+        String path = file.getName();
         return path.endsWith(".jar.pack") || path.endsWith(".jar.pack_new") ||
             path.endsWith(".jar.pack.gz")|| path.endsWith(".jar.pack.gz_new");
     }
diff --git a/core/src/main/java/com/threerings/getdown/tools/Differ.java b/core/src/main/java/com/threerings/getdown/tools/Differ.java
index 31a0f0a..97a7d29 100644
--- a/core/src/main/java/com/threerings/getdown/tools/Differ.java
+++ b/core/src/main/java/com/threerings/getdown/tools/Differ.java
@@ -88,8 +88,8 @@ public class Differ
         }
     }
 
-    protected static void createPatch(File patch, ArrayList<Resource> orsrcs,
-                                      ArrayList<Resource> nrsrcs, boolean verbose)
+    protected void createPatch (File patch, ArrayList<Resource> orsrcs,
+                                ArrayList<Resource> nrsrcs, boolean verbose)
         throws IOException
     {
         int version = Digest.VERSION;
@@ -165,7 +165,8 @@ public class Differ
         }
     }
 
-    protected static File rebuildJar(File target) throws IOException
+    protected File rebuildJar (File target)
+        throws IOException
     {
         File temp = File.createTempFile("differ", "jar");
         try (ZipFile jar = new ZipFile(target);
@@ -189,7 +190,8 @@ public class Differ
         return temp;
     }
 
-    protected static void jarDiff(File ofile, File nfile, ZipOutputStream jout) throws IOException
+    protected void jarDiff (File ofile, File nfile, ZipOutputStream jout)
+        throws IOException
     {
         JarDiff.createPatch(ofile.getPath(), nfile.getPath(), jout, false);
     }
@@ -197,7 +199,8 @@ public class Differ
     public static void main (String[] args)
     {
         if (args.length < 2) {
-            System.err.println("Usage: Differ [-verbose] new_vers_dir old_vers_dir");
+            System.err.println(
+                "Usage: Differ [-verbose] new_vers_dir old_vers_dir");
             System.exit(255);
         }
         Differ differ = new Differ();
diff --git a/core/src/main/java/com/threerings/getdown/tools/JarDiff.java b/core/src/main/java/com/threerings/getdown/tools/JarDiff.java
index 90ddf0c..734fc9c 100644
--- a/core/src/main/java/com/threerings/getdown/tools/JarDiff.java
+++ b/core/src/main/java/com/threerings/getdown/tools/JarDiff.java
@@ -74,16 +74,18 @@ public class JarDiff implements JarDiffCodes
     private static boolean _debug;
 
     /**
-     * Creates a patch from the two passed in files, writing the result to {@code os}.
+     * Creates a patch from the two passed in files, writing the result to <code>os</code>.
      */
     public static void createPatch (String oldPath, String newPath,
                                     OutputStream os, boolean minimal) throws IOException
     {
-        try (JarFile2 oldJar = new JarFile2(oldPath); JarFile2 newJar = new JarFile2(newPath)) {
-            final Map<String, String> moved = new HashMap<>();
-            final Set<String> implicit = new HashSet<>();
-            final Set<String> moveSrc = new HashSet<>();
-            final Set<String> newEntries = new HashSet<>();
+        try (JarFile2 oldJar = new JarFile2(oldPath);
+             JarFile2 newJar = new JarFile2(newPath)) {
+
+            HashMap<String,String> moved = new HashMap<>();
+            HashSet<String> implicit = new HashSet<>();
+            HashSet<String> moveSrc = new HashSet<>();
+            HashSet<String> newEntries = new HashSet<>();
 
             // FIRST PASS
             // Go through the entries in new jar and
@@ -128,6 +130,7 @@ public class JarDiff implements JarDiffCodes
                             // for backward compatibility
 
                             if (_debug) {
+
                                 System.out.println("NEW: "+ newname);
                             }
                             newEntries.add(newname);
@@ -141,9 +144,12 @@ public class JarDiff implements JarDiffCodes
                         }
                         // Check if this disables an implicit 'move <oldname> <oldname>'
                         if (implicit.contains(oldname) && minimal) {
+
                             if (_debug) {
                                 System.err.println("implicit.remove " + oldname);
+
                                 System.err.println("moved.put " + oldname + " " + oldname);
+
                             }
                             implicit.remove(oldname);
                             moved.put(oldname, oldname);
@@ -155,7 +161,7 @@ public class JarDiff implements JarDiffCodes
 
             // SECOND PASS: <deleted files> = <oldjarnames> - <implicitmoves> -
             // <source of move commands> - <new or modified entries>
-            final List<String> deleted = new ArrayList<>();
+            ArrayList<String> deleted = new ArrayList<>();
             for (ZipEntry oldEntry : oldJar) {
                 String oldName = oldEntry.getName();
                 if (!implicit.contains(oldName) && !moveSrc.contains(oldName)
@@ -201,11 +207,12 @@ public class JarDiff implements JarDiffCodes
     }
 
     /**
-     * Writes the index file out to {@code jos}.
-     * {@code oldEntries} gives the names of the files that were removed,
-     * {@code movedMap} maps from the new name to the old name.
+     * Writes the index file out to <code>jos</code>.
+     * <code>oldEntries</code> gives the names of the files that were removed,
+     * <code>movedMap</code> maps from the new name to the old name.
      */
-    private static void createIndex (ZipOutputStream jos, List<String> oldEntries, Map<String,String> movedMap)
+    private static void createIndex (ZipOutputStream jos, List<String> oldEntries,
+                                     Map<String,String> movedMap)
         throws IOException
     {
         StringWriter writer = new StringWriter();
@@ -236,7 +243,7 @@ public class JarDiff implements JarDiffCodes
         jos.write(bytes, 0, bytes.length);
     }
 
-    protected static void writeEscapedString (Writer writer, String string)
+    protected static Writer writeEscapedString (Writer writer, String string)
         throws IOException
     {
         int index = 0;
@@ -262,6 +269,7 @@ public class JarDiff implements JarDiffCodes
             writer.write(string);
         }
 
+        return writer;
     }
 
     private static void writeEntry (ZipOutputStream jos, ZipEntry entry, JarFile2 file)
@@ -380,7 +388,7 @@ public class JarDiff implements JarDiffCodes
 
         public String hasSameContent (JarFile2 file, ZipEntry entry) throws IOException {
             String thisName = null;
-            Long crcL = entry.getCrc();
+            Long crcL = Long.valueOf(entry.getCrc());
             // check if this jar contains files with the passed in entry's crc
             if (_crcToEntryMap.containsKey(crcL)) {
                 // get the Linked List with files with the crc
@@ -415,7 +423,7 @@ public class JarDiff implements JarDiffCodes
                 while (entries.hasMoreElements()) {
                     ZipEntry entry = entries.nextElement();
                     long crc = entry.getCrc();
-                    Long crcL = crc;
+                    Long crcL = Long.valueOf(crc);
                     if (_debug) {
                         System.out.println("\t" + entry.getName() + " CRC " + crc);
                     }
@@ -432,7 +440,7 @@ public class JarDiff implements JarDiffCodes
 
                     } else {
                         // create a new entry in the hashmap for the new key
-                        LinkedList<ZipEntry> ll = new LinkedList<ZipEntry>();
+                        LinkedList<ZipEntry> ll = new LinkedList<>();
                         ll.add(entry);
                         _crcToEntryMap.put(crcL, ll);
                     }
diff --git a/core/src/main/java/com/threerings/getdown/tools/JarDiffPatcher.java b/core/src/main/java/com/threerings/getdown/tools/JarDiffPatcher.java
index af42173..859d73e 100644
--- a/core/src/main/java/com/threerings/getdown/tools/JarDiffPatcher.java
+++ b/core/src/main/java/com/threerings/getdown/tools/JarDiffPatcher.java
@@ -41,22 +41,22 @@ public class JarDiffPatcher implements JarDiffCodes
      *
      * @throws IOException if any problem occurs during patching.
      */
-    public static void patchJar(String jarPath, String diffPath, File target, ProgressObserver observer)
+    public void patchJar (String jarPath, String diffPath, File target, ProgressObserver observer)
         throws IOException
     {
         File oldFile = new File(jarPath), diffFile = new File(diffPath);
         try (ZipFile oldJar = new ZipFile(oldFile);
             ZipFile jarDiff = new ZipFile(diffFile);
             ZipOutputStream jos = new ZipOutputStream(new FileOutputStream(target))) {
-            final Set<String> ignoreSet = new HashSet<>();
-            final Map<String, String> renameMap = new HashMap<>();
+            Set<String> ignoreSet = new HashSet<>();
+            Map<String, String> renameMap = new HashMap<>();
             determineNameMapping(jarDiff, ignoreSet, renameMap);
 
             // get all keys in renameMap
             String[] keys = renameMap.keySet().toArray(new String[renameMap.size()]);
 
             // Files to implicit move
-            final Set<String> oldjarNames  = new HashSet<>();
+            Set<String> oldjarNames  = new HashSet<>();
             Enumeration<? extends ZipEntry> oldEntries = oldJar.entries();
             if (oldEntries != null) {
                 while  (oldEntries.hasMoreElements()) {
@@ -111,7 +111,8 @@ public class JarDiffPatcher implements JarDiffCodes
                 // Get source ZipEntry
                 ZipEntry oldEntry = oldJar.getEntry(oldName);
                 if (oldEntry == null) {
-                    throw new IOException("error.badmove: " + MOVE_COMMAND + oldName + " " + newName);
+                    String moveCmd = MOVE_COMMAND + oldName + " " + newName;
+                    throw new IOException("error.badmove: " + moveCmd);
                 }
 
                 // Create dest ZipEntry
@@ -156,14 +157,14 @@ public class JarDiffPatcher implements JarDiffCodes
         }
     }
 
-    protected static void updateObserver(ProgressObserver observer, double currentSize, double size)
+    protected void updateObserver (ProgressObserver observer, double currentSize, double size)
     {
         if (observer != null) {
             observer.progress((int)(100*currentSize/size));
         }
     }
 
-    protected static void determineNameMapping(
+    protected void determineNameMapping (
         ZipFile jarDiff, Set<String> ignoreSet, Map<String, String> renameMap)
         throws IOException
     {
@@ -172,7 +173,8 @@ public class JarDiffPatcher implements JarDiffCodes
             throw new IOException("error.noindex");
         }
 
-        LineNumberReader indexReader = new LineNumberReader(new InputStreamReader(is, UTF_8));
+        LineNumberReader indexReader =
+            new LineNumberReader(new InputStreamReader(is, UTF_8));
         String line = indexReader.readLine();
         if (line == null || !line.equals(VERSION_HEADER)) {
             throw new IOException("jardiff.error.badheader: " + line);
@@ -207,11 +209,12 @@ public class JarDiffPatcher implements JarDiffCodes
         }
     }
 
-    protected static List<String> getSubpaths(String path)
+    protected List<String> getSubpaths (String path)
     {
         int index = 0;
         int length = path.length();
-        final List<String> sub = new ArrayList<>();
+        ArrayList<String> sub = new ArrayList<>();
+
         while (index < length) {
             while (index < length && Character.isWhitespace
                    (path.charAt(index))) {
@@ -251,7 +254,7 @@ public class JarDiffPatcher implements JarDiffCodes
         return sub;
     }
 
-    protected static void writeEntry(ZipOutputStream jos, ZipEntry entry, ZipFile file)
+    protected void writeEntry (ZipOutputStream jos, ZipEntry entry, ZipFile file)
         throws IOException
     {
         try (InputStream data = file.getInputStream(entry)) {
@@ -259,7 +262,7 @@ public class JarDiffPatcher implements JarDiffCodes
         }
     }
 
-    protected static void writeEntry(ZipOutputStream jos, ZipEntry entry, InputStream data)
+    protected void writeEntry (ZipOutputStream jos, ZipEntry entry, InputStream data)
         throws IOException
     {
         jos.putNextEntry(new ZipEntry(entry.getName()));
diff --git a/core/src/main/java/com/threerings/getdown/tools/Patcher.java b/core/src/main/java/com/threerings/getdown/tools/Patcher.java
index 922ebb0..fc39426 100644
--- a/core/src/main/java/com/threerings/getdown/tools/Patcher.java
+++ b/core/src/main/java/com/threerings/getdown/tools/Patcher.java
@@ -121,7 +121,8 @@ public class Patcher
         }
     }
 
-    protected void patchFile (ZipFile file, ZipEntry entry, File appdir, String path)
+    protected void patchFile (ZipFile file, ZipEntry entry,
+                              File appdir, String path)
     {
         File target = new File(appdir, path);
         File patch = new File(appdir, entry.getName());
@@ -154,7 +155,7 @@ public class Patcher
 
             // now apply the patch to create the new target file
             patcher = new JarDiffPatcher();
-            JarDiffPatcher.patchJar(otarget.getPath(), patch.getPath(), target, obs);
+            patcher.patchJar(otarget.getPath(), patch.getPath(), target, obs);
 
         } catch (IOException ioe) {
             if (patcher == null) {
diff --git a/core/src/main/java/com/threerings/getdown/util/FileUtil.java b/core/src/main/java/com/threerings/getdown/util/FileUtil.java
index 08f4ac4..06ac41c 100644
--- a/core/src/main/java/com/threerings/getdown/util/FileUtil.java
+++ b/core/src/main/java/com/threerings/getdown/util/FileUtil.java
@@ -120,9 +120,7 @@ public final class FileUtil
     {
         List<String> lines = new ArrayList<>();
         try (BufferedReader bin = new BufferedReader(in)) {
-            for (String line; (line = bin.readLine()) != null;) {
-                lines.add(line);
-            }
+            for (String line = null; (line = bin.readLine()) != null; lines.add(line)) {}
         }
         return lines;
     }
@@ -142,9 +140,8 @@ public final class FileUtil
                     File efile = new File(target, entry.getName());
                     if (efile.exists()) {
                         for (File f : efile.listFiles()) {
-                            if (!f.isDirectory()) {
-                                f.delete();
-                            }
+                            if (!f.isDirectory())
+                            f.delete();
                         }
                     }
                 }