DroidFish: Code cleanup.

DroidFish/src/org/petero/droidfish/engine/DroidBook.java

@@ -66,6 +66,8 @@ public final class DroidBook {
     private BookOptions options = null;
 
     private static final DroidBook INSTANCE = new DroidBook();
+
+    /** Get singleton instance. */
     public static DroidBook getInstance() {
         return INSTANCE;
     }
@@ -75,7 +77,7 @@ public final class DroidBook {
     }
 
     /** Set opening book options. */
-    public final void setOptions(BookOptions options) {
+    public final synchronized void setOptions(BookOptions options) {
         this.options = options;
         if (CtgBook.canHandle(options))
             externalBook = new CtgBook();
@@ -88,7 +90,7 @@ public final class DroidBook {
     }
 
     /** Return a random book move for a position, or null if out of book. */
-    public final Move getBookMove(Position pos) {
+    public final synchronized Move getBookMove(Position pos) {
         if ((options != null) && (pos.fullMoveCounter > options.maxLength))
             return null;
         List<BookEntry> bookMoves = getBook().getBookEntries(pos);
@@ -121,24 +123,8 @@ public final class DroidBook {
         return bookMoves.get(nMoves-1).move;
     }
 
-    private final double scaleWeight(double w) {
-        if (w <= 0)
-            return 0;
-        if (options == null)
-            return w;
-        return Math.pow(w, Math.exp(-options.random));
-    }
-
-    final private IOpeningBook getBook() {
-        if (externalBook.enabled()) {
-            return externalBook;
-        } else {
-            return internalBook;
-        }
-    }
-
     /** Return all book moves, both as a formatted string and as a list of moves. */
-    public final Pair<String,ArrayList<Move>> getAllBookMoves(Position pos) {
+    public final synchronized Pair<String,ArrayList<Move>> getAllBookMoves(Position pos) {
         StringBuilder ret = new StringBuilder();
         ArrayList<Move> bookMoveList = new ArrayList<Move>();
         List<BookEntry> bookMoves = getBook().getBookEntries(pos);
@@ -184,6 +170,22 @@ public final class DroidBook {
         return new Pair<String, ArrayList<Move>>(ret.toString(), bookMoveList);
     }
 
+    private final double scaleWeight(double w) {
+        if (w <= 0)
+            return 0;
+        if (options == null)
+            return w;
+        return Math.pow(w, Math.exp(-options.random));
+    }
+
+    private final IOpeningBook getBook() {
+        if (externalBook.enabled()) {
+            return externalBook;
+        } else {
+            return internalBook;
+        }
+    }
+
     /** Creates the book.bin file. */
     public static void main(String[] args) throws IOException {
         List<Byte> binBook = createBinBook();
@@ -196,7 +198,7 @@ public final class DroidBook {
         out.close();
     }
 
-    public static List<Byte> createBinBook() {
+    private static final List<Byte> createBinBook() {
         List<Byte> binBook = new ArrayList<Byte>(0);
         try {
             InputStream inStream = new Object().getClass().getResourceAsStream("/book.txt");
@@ -225,7 +227,7 @@ public final class DroidBook {
     }
 
     /** Add a sequence of moves, starting from the initial position, to the binary opening book. */
-    private static boolean addBookLine(String line, List<Byte> binBook) throws ChessParseError {
+    private static final boolean addBookLine(String line, List<Byte> binBook) throws ChessParseError {
         Position pos = TextIO.readFEN(TextIO.startPosFEN);
         UndoInfo ui = new UndoInfo();
         String[] strMoves = line.split(" ");
@@ -251,7 +253,7 @@ public final class DroidBook {
         return true;
     }
 
-    private static int pieceToProm(int p) {
+    private static final int pieceToProm(int p) {
         switch (p) {
         case Piece.WQUEEN: case Piece.BQUEEN:
             return 1;

DroidFish/src/org/petero/droidfish/engine/DroidComputerPlayer.java

@@ -101,29 +101,18 @@ public class DroidComputerPlayer {
     }
 
     /** Get engine reported name, including strength setting. */
-    public synchronized String getEngineName() {
+    public final synchronized String getEngineName() {
         String ret = engineName;
         if (strength < 1000)
             ret += String.format(" (%.1f%%)", strength * 0.1);
         return ret;
     }
 
-    /** Clear transposition table. */
+    /** Clear transposition table. Takes effect when next search started. */
-    public final void clearTT() {
+    public final synchronized void clearTT() {
         newGame = true;
     }
 
-    /** Sends "ucinewgame" to engine if clearTT() has previously been called. */
-    public final void maybeNewGame() {
-        if (newGame) {
-            newGame = false;
-            if (uciEngine != null) {
-                uciEngine.writeLineToEngine("ucinewgame");
-                syncReady();
-            }
-        }
-    }
-
     /** Sends "ponderhit" command to engine. */
     public final synchronized void ponderHit(Position pos, Move ponderMove) {
         havePonderHit = true;
@@ -320,7 +309,18 @@ public class DroidComputerPlayer {
         }
     }
 
-    private static int getNumCPUs() {
+    /** Sends "ucinewgame" to engine if clearTT() has previously been called. */
+    private final void maybeNewGame() {
+        if (newGame) {
+            newGame = false;
+            if (uciEngine != null) {
+                uciEngine.writeLineToEngine("ucinewgame");
+                syncReady();
+            }
+        }
+    }
+
+    private static final int getNumCPUs() {
         int nCPUsFromProc = 1;
         try {
             FileReader fr = new FileReader("/proc/stat");
@@ -428,7 +428,7 @@ public class DroidComputerPlayer {
      * @param move The move that may have to be made before claiming draw.
      * @return The draw string that claims the draw, or empty string if draw claim not valid.
      */
-    private String canClaimDraw(Position pos, long[] posHashList, int posHashListSize, Move move) {
+    private final String canClaimDraw(Position pos, long[] posHashList, int posHashListSize, Move move) {
         String drawStr = "";
         if (canClaimDraw50(pos)) {
             drawStr = "draw 50";