diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java
new file mode 100644
index 0000000..83c5d9a
--- /dev/null
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.android.inputmethod.latin.dicttool;
+
+import java.io.IOException;
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+* Class grouping utilities for offline dictionary making.
+*
+* Those should not be used on-device, essentially because they are quite
+* liberal about I/O and performance.
+*/
+public class BinaryDictOffdeviceUtils {
+    public static void copy(final InputStream input, final OutputStream output) throws IOException {
+        final byte[] buffer = new byte[1000];
+        final BufferedInputStream in = new BufferedInputStream(input);
+        final BufferedOutputStream out = new BufferedOutputStream(output);
+        for (int readBytes = in.read(buffer); readBytes >= 0; readBytes = in.read(buffer))
+            output.write(buffer, 0, readBytes);
+        in.close();
+        out.close();
+    }
+}
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Compress.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Compress.java
index 3cb0a12..49e90ad 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Compress.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Compress.java
@@ -36,14 +36,6 @@
         return new GZIPInputStream(in);
     }
 
-    public static void copy(final InputStream input, final OutputStream output) throws IOException {
-        final byte[] buffer = new byte[1000];
-        for (int readBytes = input.read(buffer); readBytes >= 0; readBytes = input.read(buffer))
-            output.write(buffer, 0, readBytes);
-        input.close();
-        output.close();
-    }
-
     static public class Compressor extends Dicttool.Command {
         public static final String COMMAND = "compress";
         public static final String STDIN_OR_STDOUT = "-";
@@ -66,7 +58,7 @@
                     : new FileInputStream(new File(inFilename));
             final OutputStream output = outFilename.equals(STDIN_OR_STDOUT) ? System.out
                     : new FileOutputStream(new File(outFilename));
-            copy(input, new GZIPOutputStream(output));
+            BinaryDictOffdeviceUtils.copy(input, new GZIPOutputStream(output));
         }
     }
 
@@ -92,7 +84,7 @@
                     : new FileInputStream(new File(inFilename));
             final OutputStream output = outFilename.equals(STDIN_OR_STDOUT) ? System.out
                     : new FileOutputStream(new File(outFilename));
-            copy(new GZIPInputStream(input), output);
+            BinaryDictOffdeviceUtils.copy(new GZIPInputStream(input), output);
         }
     }
 }