Change cloning mechanism, change many fields to final

Author: sfuhrm

sudoku/src/main/java/de/sfuhrm/sudoku/CachedGameMatrixImpl.java

@@ -35,17 +35,17 @@ class CachedGameMatrixImpl extends GameMatrixImpl {
      * A set 2-bit means that the digit 2 is free for use.
      * And so on.
      */
-    private int[] rowFree;
+    private final int[] rowFree;
 
     /** Buffered free masks per column.
      * @see #rowFree
      */
-    private int[] columnFree;
+    private final int[] columnFree;
 
     /** Buffered free masks per block.
      * @see #rowFree
      */
-    private int[][] blockFree;
+    private final int[][] blockFree;
 
     /** The count of non-{@link GameSchema#getUnsetValue() unset} cells.
      * @see #getSetCount()
@@ -77,6 +77,18 @@ class CachedGameMatrixImpl extends GameMatrixImpl {
         }
     }
 
+    /**
+     * Clone constructor.
+     * @param source the source to initialize with.
+     */
+    CachedGameMatrixImpl(final CachedGameMatrixImpl source) {
+        super(source);
+
+        blockFree = QuadraticArrays.cloneArray(source.blockFree);
+        columnFree = Arrays.copyOf(source.columnFree, source.columnFree.length);
+        rowFree = Arrays.copyOf(source.rowFree, source.rowFree.length);
+    }
+
     @Override
     int getBlockFreeMask(final int row, final int column) {
         final int blockWidth = getSchema().getBlockWidth();
@@ -149,11 +161,6 @@ public int getSetCount() {
 
     @Override
     public CachedGameMatrixImpl clone() {
-        CachedGameMatrixImpl clone;
-        clone = (CachedGameMatrixImpl) super.clone();
-        clone.blockFree = QuadraticArrays.cloneArray(blockFree);
-        clone.columnFree = Arrays.copyOf(columnFree, columnFree.length);
-        clone.rowFree = Arrays.copyOf(rowFree, rowFree.length);
-        return clone;
+        return new CachedGameMatrixImpl(this);
     }
 }

sudoku/src/main/java/de/sfuhrm/sudoku/GameMatrixImpl.java

@@ -39,7 +39,7 @@ class GameMatrixImpl implements Cloneable, GameMatrix {
      * The values 1-9 mean the corresponding cell
      * value.
      */
-    private byte[][] data;
+    private final byte[][] data;
 
     /**
      * Creates an empty riddle.
@@ -52,6 +52,16 @@ class GameMatrixImpl implements Cloneable, GameMatrix {
         data = new byte[inGameSchema.getWidth()][inGameSchema.getWidth()];
     }
 
+    /**
+     * Clone constructor.
+     * @param source source matrix to init with.
+     * @see #setAll(byte[][])
+     */
+    GameMatrixImpl(final GameMatrixImpl source) {
+        this.gameSchema = source.gameSchema;
+        data = QuadraticArrays.cloneArray(source.data);
+    }
+
     /** Sets all cells to the given values.
      * @param initializationData initialization data with the first dimension
      * being the rows and the second dimension being the columns.
@@ -208,15 +218,7 @@ public final boolean equals(final Object obj) {
 
     @Override
     public GameMatrixImpl clone() {
-        GameMatrixImpl clone;
-        try {
-            clone = (GameMatrixImpl) super.clone();
-            clone.data = QuadraticArrays.cloneArray(data);
-        } catch (CloneNotSupportedException ex) {
-            throw new IllegalStateException(ex);
-        }
-
-        return clone;
+        return new GameMatrixImpl(this);
     }
 
     /** Finds the duplicate bits.

sudoku/src/main/java/de/sfuhrm/sudoku/RiddleImpl.java

@@ -31,7 +31,7 @@ class RiddleImpl extends GameMatrixImpl implements Riddle {
      * Whether the cell is writable. Pre-defined cells are only readable, use
      * settable cells are writable.
      */
-    private boolean[][] writeable;
+    private final boolean[][] writeable;
 
     /**
      * Creates an empty full-writable riddle.
@@ -49,6 +49,15 @@ class RiddleImpl extends GameMatrixImpl implements Riddle {
         }
     }
 
+    /**
+     * Clone constructor.
+     * @param source source data to init with.
+     */
+    RiddleImpl(final RiddleImpl source) {
+        super(source);
+        writeable = QuadraticArrays.cloneArray(source.writeable);
+    }
+
     /**
      * Get whether a certain field is writable.
      * @param row the row of the cell to get the writability for.
@@ -75,9 +84,6 @@ public final void setWritable(final int row,
 
     @Override
     public final RiddleImpl clone() {
-        RiddleImpl clone;
-        clone = (RiddleImpl) super.clone();
-        clone.writeable = QuadraticArrays.cloneArray(writeable);
-        return clone;
+        return new RiddleImpl(this);
     }
 }