Add transformation methods to table classes

src/main/java/pkovacs/util/data/AbstractTable.java

@@ -34,6 +34,8 @@ public int size() {
 
     abstract void set0(int row, int col, T value);
 
+    abstract AbstractTable<T> newInstance(int rowCount, int colCount, BiFunction<Integer, Integer, T> function);
+
     /**
      * Returns true if this table contains the given cell.
      */
@@ -119,4 +121,48 @@ public void updateAll(Function<? super T, ? extends T> function) {
         }
     }
 
+    /**
+     * Mirrors this table horizontally: the row indices remain the same, while column indices are flipped.
+     * A new table is generated and returned, this table is not changed.
+     */
+    public AbstractTable<T> mirrorHorizontally() {
+        int colCount = colCount();
+        return newInstance(rowCount(), colCount, (i, j) -> get0(i, colCount - 1 - j));
+    }
+
+    /**
+     * Mirrors this table vertically: the column indices remain the same, while the row indices are flipped.
+     * A new table is generated and returned, this table is not changed.
+     */
+    public AbstractTable<T> mirrorVertically() {
+        int rowCount = rowCount();
+        return newInstance(rowCount, colCount(), (i, j) -> get0(rowCount - 1 - i, j));
+    }
+
+    /**
+     * Rotates this table to the right (clockwise).
+     * A new table is generated and returned, this table is not changed.
+     */
+    public AbstractTable<T> rotateRight() {
+        int rowCount = rowCount();
+        return newInstance(colCount(), rowCount(), (i, j) -> get0(rowCount - 1 - j, i));
+    }
+
+    /**
+     * Rotates this table to the left (counter-clockwise).
+     * A new table is generated and returned, this table is not changed.
+     */
+    public AbstractTable<T> rotateLeft() {
+        int colCount = colCount();
+        return newInstance(colCount(), rowCount(), (i, j) -> get0(j, colCount - 1 - i));
+    }
+
+    /**
+     * Transposes this table: turns rows into columns and vice versa.
+     * A new table is generated and returned, this table is not changed.
+     */
+    public AbstractTable<T> transpose() {
+        return newInstance(colCount(), rowCount(), (i, j) -> get0(j, i));
+    }
+
 }

src/main/java/pkovacs/util/data/CharTable.java

@@ -88,6 +88,11 @@ void set0(int row, int col, Character value) {
         data[row][col] = value;
     }
 
+    @Override
+    CharTable newInstance(int rowCount, int colCount, BiFunction<Integer, Integer, Character> function) {
+        return new CharTable(rowCount, colCount, function);
+    }
+
     /**
      * Returns the {@code char[][]} array that backs this table. Changes to the returned array are reflected in the
      * table, and vice-versa.
@@ -160,6 +165,31 @@ public Stream<Character> values(int startRow, int startCol, int endRow, int endC
         return cells(startRow, startCol, endRow, endCol).map(this::get);
     }
 
+    @Override
+    public CharTable mirrorHorizontally() {
+        return (CharTable) super.mirrorHorizontally();
+    }
+
+    @Override
+    public CharTable mirrorVertically() {
+        return (CharTable) super.mirrorVertically();
+    }
+
+    @Override
+    public CharTable rotateRight() {
+        return (CharTable) super.rotateRight();
+    }
+
+    @Override
+    public CharTable rotateLeft() {
+        return (CharTable) super.rotateLeft();
+    }
+
+    @Override
+    public CharTable transpose() {
+        return (CharTable) super.transpose();
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {

src/main/java/pkovacs/util/data/IntTable.java

@@ -86,6 +86,11 @@ void set0(int row, int col, Integer value) {
         data[row][col] = value;
     }
 
+    @Override
+    IntTable newInstance(int rowCount, int colCount, BiFunction<Integer, Integer, Integer> function) {
+        return new IntTable(rowCount, colCount, function);
+    }
+
     /**
      * Returns the {@code int[][]} array that backs this table. Changes to the returned array are reflected in the
      * table, and vice-versa.
@@ -193,6 +198,31 @@ public int max() {
         return values().max().orElseThrow();
     }
 
+    @Override
+    public IntTable mirrorHorizontally() {
+        return (IntTable) super.mirrorHorizontally();
+    }
+
+    @Override
+    public IntTable mirrorVertically() {
+        return (IntTable) super.mirrorVertically();
+    }
+
+    @Override
+    public IntTable rotateRight() {
+        return (IntTable) super.rotateRight();
+    }
+
+    @Override
+    public IntTable rotateLeft() {
+        return (IntTable) super.rotateLeft();
+    }
+
+    @Override
+    public IntTable transpose() {
+        return (IntTable) super.transpose();
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {

src/main/java/pkovacs/util/data/Table.java

@@ -84,6 +84,11 @@ void set0(int row, int col, T value) {
         data[row][col] = value;
     }
 
+    @Override
+    Table<T> newInstance(int rowCount, int colCount, BiFunction<Integer, Integer, T> function) {
+        return new Table<T>(rowCount, colCount, function);
+    }
+
     /**
      * Returns the value associated with the specified cell.
      */
@@ -148,6 +153,31 @@ public Stream<T> values(int startRow, int startCol, int endRow, int endCol) {
         return cells(startRow, startCol, endRow, endCol).map(this::get);
     }
 
+    @Override
+    public Table<T> mirrorHorizontally() {
+        return (Table<T>) super.mirrorHorizontally();
+    }
+
+    @Override
+    public Table<T> mirrorVertically() {
+        return (Table<T>) super.mirrorVertically();
+    }
+
+    @Override
+    public Table<T> rotateRight() {
+        return (Table<T>) super.rotateRight();
+    }
+
+    @Override
+    public Table<T> rotateLeft() {
+        return (Table<T>) super.rotateLeft();
+    }
+
+    @Override
+    public Table<T> transpose() {
+        return (Table<T>) super.transpose();
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {

src/test/java/pkovacs/util/data/AbstractTableTest.java

@@ -99,6 +99,40 @@ void testCellNeighbors() {
                 table.extendedNeighborCells(new Tile(2, 1)).toList());
     }
 
+    @Test
+    void testTransformations() {
+        var table = createTestTable(3, 4);
+        var transposed = table.transpose();
+        var right = table.rotateRight();
+        var left = table.rotateLeft();
+
+        assertEquals(table.rowCount(), transposed.colCount());
+        assertEquals(table.colCount(), transposed.rowCount());
+        assertEquals(table.rowCount(), right.colCount());
+        assertEquals(table.colCount(), right.rowCount());
+        assertEquals(table.rowCount(), left.colCount());
+        assertEquals(table.colCount(), left.rowCount());
+
+        assertNotEquals(transposed, right);
+        assertNotEquals(transposed, left);
+        assertNotEquals(right, left);
+
+        assertEquals(table, transposed.transpose());
+        assertEquals(table, right.rotateLeft());
+        assertEquals(table, left.rotateRight());
+        assertEquals(table, right.rotateRight().rotateRight().rotateRight());
+        assertEquals(table, left.rotateLeft().rotateLeft().rotateLeft());
+        assertEquals(table, right.rotateRight().mirrorVertically().mirrorHorizontally());
+        assertEquals(table, left.rotateLeft().mirrorVertically().mirrorHorizontally());
+
+        assertEquals(right.rotateRight(), left.rotateLeft());
+
+        assertEquals(transposed, right.mirrorHorizontally());
+        assertEquals(transposed, left.mirrorVertically());
+        assertEquals(transposed, table.mirrorVertically().rotateRight());
+        assertEquals(transposed, table.mirrorHorizontally().rotateLeft());
+    }
+
     @Test
     void testEqualsAndHashCode() {
         var table1 = createTestTable(3, 4);

src/test/java/pkovacs/util/data/IntTableTest.java

@@ -108,6 +108,12 @@ void testToString() {
         table3.set(1, 1, 424242);
         assertEquals("     0     -1      2     -3\n  -100 424242   -102    103\n   200   -201    202   -203\n",
                 table3.toString());
+
+        var table4 = createTestTable(3, 4).transpose();
+        var table5 = createTestTable(3, 4).rotateRight();
+
+        assertEquals("  0 100 200\n  1 101 201\n  2 102 202\n  3 103 203\n", table4.toString());
+        assertEquals("200 100   0\n201 101   1\n202 102   2\n203 103   3\n", table5.toString());
     }
 
     private static void assertContentEquals(int[][] expected, IntTable table) {