make md5sum calculation available everywhere

I want to log sums to see when they arrive on relay. And also add some
missing @Overrides I noticed.

xwords4/android/app/src/main/java/org/eehouse/android/xw4/CommsTransport.java

@@ -347,9 +347,10 @@ public class CommsTransport implements TransportProcs,
     }
 
     // TransportProcs interface
-
+    @Override
     public int getFlags() { return COMMS_XPORT_FLAGS_NONE; }
 
+    @Override
     public int transportSend( byte[] buf, String msgNo, CommsAddrRec addr,
                               CommsConnType conType, int gameID )
     {
@@ -386,17 +387,20 @@ public class CommsTransport implements TransportProcs,
         return nSent;
     }
 
+    @Override
     public void relayConnd( String room, int devOrder, boolean allHere,
                             int nMissing )
     {
         m_tpHandler.tpmRelayConnd( room, devOrder, allHere, nMissing );
     }
 
+    @Override
     public void relayErrorProc( XWRELAY_ERROR relayErr )
     {
         m_tpHandler.tpmRelayErrorProc( relayErr );
     }
 
+    @Override
     public boolean relayNoConnProc( byte[] buf, String msgNo, String relayID )
     {
         Assert.fail();

xwords4/android/app/src/main/java/org/eehouse/android/xw4/MultiMsgSink.java

@@ -84,9 +84,10 @@ public class MultiMsgSink implements TransportProcs {
     }
 
     /***** TransportProcs interface *****/
-
+    @Override
     public int getFlags() { return COMMS_XPORT_FLAGS_HASNOCONN; }
 
+    @Override
     public int transportSend( byte[] buf, String msgNo, CommsAddrRec addr,
                               CommsConnType typ, int gameID )
     {
@@ -118,15 +119,18 @@ public class MultiMsgSink implements TransportProcs {
         return nSent;
     }
 
+    @Override
     public void relayErrorProc( XWRELAY_ERROR relayErr )
     {
     }
 
+    @Override
     public void relayConnd( String room, int devOrder, boolean allHere,
                             int nMissing )
     {
     }
 
+    @Override
     public boolean relayNoConnProc( byte[] buf, String msgNo, String relayID )
     {
         // Assert.fail();

xwords4/android/app/src/main/java/org/eehouse/android/xw4/Utils.java

@@ -68,13 +68,13 @@ import java.io.InputStreamReader;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.io.Serializable;
+import java.security.MessageDigest;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Random;
 
-
 import org.eehouse.android.xw4.Perms23.Perm;
 import org.eehouse.android.xw4.jni.CommonPrefs;
 import org.eehouse.android.xw4.loc.LocUtils;
@@ -359,6 +359,32 @@ public class Utils {
         return str;
     }
 
+    public static String getMD5SumFor( byte[] bytes )
+    {
+        String result = null;
+        if ( bytes != null ) {
+            byte[] digest = null;
+            try {
+                MessageDigest md = MessageDigest.getInstance("MD5");
+                byte[] buf = new byte[128];
+                int nLeft = bytes.length;
+                int offset = 0;
+                while ( 0 < nLeft ) {
+                    int len = Math.min( buf.length, nLeft );
+                    System.arraycopy( bytes, offset, buf, 0, len );
+                    md.update( buf, 0, len );
+                    nLeft -= len;
+                    offset += len;
+                }
+                digest = md.digest();
+            } catch ( java.security.NoSuchAlgorithmException nsae ) {
+                Log.ex( TAG, nsae );
+            }
+            result = Utils.digestToString( digest );
+        }
+        return result;
+    }
+
     public static void setChecked( View parent, int id, boolean value )
     {
         CheckBox cbx = (CheckBox)parent.findViewById( id );

xwords4/android/app/src/main/java/org/eehouse/android/xw4/jni/JNIUtilsImpl.java

@@ -30,7 +30,6 @@ import org.eehouse.android.xw4.Utils;
 
 import java.io.ByteArrayInputStream;
 import java.io.InputStreamReader;
-import java.security.MessageDigest;
 import java.util.ArrayList;
 
 public class JNIUtilsImpl implements JNIUtils {
@@ -62,6 +61,7 @@ public class JNIUtilsImpl implements JNIUtils {
      * <letter>[<delim><letter]*, so for each loop until the delim
      * isn't found.
      */
+    @Override
     public String[][] splitFaces( byte[] chars, boolean isUTF8 )
     {
         ArrayList<String[]> faces = new ArrayList<String[]>();
@@ -130,32 +130,13 @@ public class JNIUtilsImpl implements JNIUtils {
         faces.add( face.toArray( new String[face.size()] ) );
     }
 
+    @Override
     public String getMD5SumFor( byte[] bytes )
     {
-        String result = null;
+        return Utils.getMD5SumFor( bytes );
-        if ( bytes != null ) {
-            byte[] digest = null;
-            try {
-                MessageDigest md = MessageDigest.getInstance("MD5");
-                byte[] buf = new byte[128];
-                int nLeft = bytes.length;
-                int offset = 0;
-                while ( 0 < nLeft ) {
-                    int len = Math.min( buf.length, nLeft );
-                    System.arraycopy( bytes, offset, buf, 0, len );
-                    md.update( buf, 0, len );
-                    nLeft -= len;
-                    offset += len;
-                }
-                digest = md.digest();
-            } catch ( java.security.NoSuchAlgorithmException nsae ) {
-                Log.ex( TAG, nsae );
-            }
-            result = Utils.digestToString( digest );
-        }
-        return result;
     }
 
+    @Override
     public String getMD5SumFor( String dictName, byte[] bytes )
     {
         String result = null;