diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
index 05f2d933c..ee0e9cd7e 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
@@ -565,6 +565,7 @@ public final class BinaryDictIOUtils {
         return size;
     }
 
+    @SuppressWarnings("unused")
     private static void updateForwardLink(final FusionDictionaryBufferInterface buffer,
             final int nodeOriginAddress, final int newNodeAddress,
             final FormatOptions formatOptions) {
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
index 031306e1d..d1a3c7b0a 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
@@ -77,12 +77,12 @@ public final class BinaryDictInputOutput {
 
         @Override
         public int readUnsignedByte() {
-            return ((int)mBuffer.get()) & 0xFF;
+            return mBuffer.get() & 0xFF;
         }
 
         @Override
         public int readUnsignedShort() {
-            return ((int)mBuffer.getShort()) & 0xFFFF;
+            return mBuffer.getShort() & 0xFFFF;
         }
 
         @Override
@@ -474,11 +474,8 @@ public final class BinaryDictInputOutput {
         }
     }
 
-    private static final int SINT8_MAX = 0x7F;
-    private static final int SINT16_MAX = 0x7FFF;
     private static final int SINT24_MAX = 0x7FFFFF;
     private static final int MSB8 = 0x80;
-    private static final int MSB16 = 0x8000;
     private static final int MSB24 = 0x800000;
 
     // End utility methods.
@@ -1711,7 +1708,7 @@ public final class BinaryDictInputOutput {
      *
      * Concretely this only tests the magic number.
      *
-     * @param filename The name of the file to test.
+     * @param file The file to test.
      * @return true if it's a binary dictionary, false otherwise
      */
     public static boolean isBinaryDictionary(final File file) {
@@ -1751,8 +1748,7 @@ public final class BinaryDictInputOutput {
             final int bigramFrequency) {
         final float stepSize = (FormatSpec.MAX_TERMINAL_FREQUENCY - unigramFrequency)
                 / (1.5f + FormatSpec.MAX_BIGRAM_FREQUENCY);
-        final float resultFreqFloat = (float)unigramFrequency
-                + stepSize * (bigramFrequency + 1.0f);
+        final float resultFreqFloat = unigramFrequency + stepSize * (bigramFrequency + 1.0f);
         return (int)resultFreqFloat;
     }
 }
diff --git a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
index 93db8e833..c588824fe 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
@@ -16,7 +16,6 @@
 
 package com.android.inputmethod.latin.makedict;
 
-import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.Constants;
 
 import java.util.ArrayList;
@@ -158,16 +157,15 @@ public final class FusionDictionary implements Iterable<Word> {
         public ArrayList<WeightedString> getShortcutTargets() {
             // We don't want write permission to escape outside the package, so we return a copy
             if (null == mShortcutTargets) return null;
-            final ArrayList<WeightedString> copyOfShortcutTargets = new ArrayList<WeightedString>();
-            copyOfShortcutTargets.addAll(mShortcutTargets);
+            final ArrayList<WeightedString> copyOfShortcutTargets =
+                    new ArrayList<WeightedString>(mShortcutTargets);
             return copyOfShortcutTargets;
         }
 
         public ArrayList<WeightedString> getBigrams() {
             // We don't want write permission to escape outside the package, so we return a copy
             if (null == mBigrams) return null;
-            final ArrayList<WeightedString> copyOfBigrams = new ArrayList<WeightedString>();
-            copyOfBigrams.addAll(mBigrams);
+            final ArrayList<WeightedString> copyOfBigrams = new ArrayList<WeightedString>(mBigrams);
             return copyOfBigrams;
         }
 
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java
index 4573fa6f7..0803b08d5 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/BinaryDictOffdeviceUtils.java
@@ -17,7 +17,6 @@
 package com.android.inputmethod.latin.dicttool;
 
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput;
-import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.ByteBufferWrapper;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
 
@@ -33,7 +32,6 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import java.nio.channels.FileChannel;
-import java.nio.channels.FileChannel.MapMode;
 import java.util.ArrayList;
 
 import javax.xml.parsers.ParserConfigurationException;
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java
index ad5f4e2b2..9548f2509 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Diff.java
@@ -95,7 +95,7 @@ public class Diff extends Dicttool.Command {
                     + dict1.mOptions.mGermanUmlautProcessing);
         }
         final HashMap<String, String> options1 =
-                (HashMap<String, String>)dict1.mOptions.mAttributes.clone();
+                new HashMap<String, String>(dict1.mOptions.mAttributes);
         for (final String optionKey : dict0.mOptions.mAttributes.keySet()) {
             if (!dict0.mOptions.mAttributes.get(optionKey).equals(
                     dict1.mOptions.mAttributes.get(optionKey))) {
@@ -112,7 +112,7 @@ public class Diff extends Dicttool.Command {
 
     private static void diffWords(final FusionDictionary dict0, final FusionDictionary dict1) {
         for (final Word word0 : dict0) {
-            final CharGroup word1 = dict1.findWordInTree(dict1.mRoot, word0.mWord);
+            final CharGroup word1 = FusionDictionary.findWordInTree(dict1.mRoot, word0.mWord);
             if (null == word1) {
                 // This word is not in dict1
                 System.out.println("Deleted: " + word0.mWord + " " + word0.mFrequency);
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java
index 6f1c020f2..7f25818fb 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/Info.java
@@ -63,7 +63,7 @@ public class Info extends Dicttool.Command {
     }
 
     private static void showWordInfo(final FusionDictionary dict, final String word) {
-        final CharGroup group = dict.findWordInTree(dict.mRoot, word);
+        final CharGroup group = FusionDictionary.findWordInTree(dict.mRoot, word);
         if (null == group) {
             System.out.println(word + " is not in the dictionary");
             return;