lucene4: finish org.elasticsearch.common.compress cleanup

src/main/java/org/elasticsearch/common/compress/CompressedDirectory.java

@@ -73,7 +73,8 @@ public class CompressedDirectory extends Directory implements ForceSyncDirectory
     @Override
     public long fileLength(String name) throws IOException {
         if (actualLength && decompressExtensions.contains(getExtension(name))) {
-            IndexInput in = openInput(name);
+            // LUCENE 4 UPGRADE: Is this the right IOContext?
+            IndexInput in = openInput(name, IOContext.READONCE);
             try {
                 return in.length();
             } catch (Exception e) {

src/main/java/org/elasticsearch/common/compress/lzf/LZFCompressedIndexInput.java

@@ -65,7 +65,7 @@ public class LZFCompressedIndexInput extends CompressedIndexInput<LZFCompressorC
     }
 
     @Override
-    public Object clone() {
+    public IndexInput clone() {
         LZFCompressedIndexInput cloned = (LZFCompressedIndexInput) super.clone();
         cloned.inputBuffer = new byte[LZFChunk.MAX_CHUNK_LEN];
         return cloned;

src/main/java/org/elasticsearch/common/compress/snappy/SnappyCompressedIndexInput.java

@@ -59,7 +59,7 @@ public abstract class SnappyCompressedIndexInput extends CompressedIndexInput<Sn
     }
 
     @Override
-    public Object clone() {
+    public IndexInput clone() {
         SnappyCompressedIndexInput cloned = (SnappyCompressedIndexInput) super.clone();
         cloned.inputBuffer = new byte[inputBuffer.length];
         return cloned;