[Ch6] GameHelper: Tests for the place method (9397fc8d) · Commits · examples / Head First Java 3rd Edition

src/main/java/ch6/GameHelper.java

+10 −16

Changes for src/main/java/ch6/GameHelper.java: 10 added lines, 16 removed lines.
Original line number	Diff line number	Diff line
		@@ -26,7 +26,6 @@ public class GameHelper {
		}

		public ArrayList<String> placeStartup(int startupSize) {
		ArrayList<String> alphaCells = new ArrayList<String>();
		// holds index to grid (0 - 48)
		int[] startupCoords = new int[startupSize]; // current candidate co-ordinates
		int attempts = 0; // current attempts counter
		@@ -41,7 +40,6 @@ public class GameHelper {
		success = horizontalStartupFits(location, startupSize);
		} else{
		success = verticalStartupFits(location, startupSize);

		}

		if (success) {
		@@ -50,8 +48,8 @@ public class GameHelper {
		} // end while
		System.out.println(this);

		ArrayList<String> alphaCells = new ArrayList<String>();
		for (int index : startupCoords) { // turn location into 'a0'-style startupCoords
		grid[index] = 1; // mark master grid position as ‘used'
		String alphaCoords = getAlphaCoordsFromIndex(index);
		alphaCells.add(alphaCoords);
		}
		@@ -65,11 +63,10 @@ public class GameHelper {
		int column = index % GRID_LENGTH; // get numeric column value

		String letter = ALPHABET.substring(column, column + 1); // convert column index to letter
		String alphaCoords = letter + row;
		return alphaCoords;
		return letter + row;
		}

		private boolean bruteForcePlace(int startupSize, int[] startupCoords, int increment, int location) {
		boolean bruteForcePlace(int startupSize, int[] startupCoords, int increment, int location) {
		System.out.println("startupSize = " + startupSize + ", startupCoords = " + Arrays.toString(startupCoords) + ", increment = " + increment + ", location = " + location);
		int k = 0;
		for (int j = location; k < startupSize; j += increment) {
		@@ -84,25 +81,22 @@ public class GameHelper {
		return false;
		}
		}
		// this is awful, more than one iteration
		for (int index : startupCoords) {
		grid[index] = 1; // mark master grid position as ‘used'
		}

		return true;
		}

		boolean horizontalStartupFits(int location, int startupSize) {
		int finalLocation = location + (HORIZONTAL.getIncrement() * startupSize);
		if (calculateRowFromIndex(location) != calculateRowFromIndex(finalLocation)) { // end position is on a different row to start position
		System.out.println("location = " + location + ", startupSize = " + startupSize);
		return false;
		}
		return true;
		return calculateRowFromIndex(location) == calculateRowFromIndex(finalLocation); // check end is on same row as start
		}

		boolean verticalStartupFits(int location, int startupSize) {
		int finalLocation = location + (VERTICAL.getIncrement() * startupSize);
		if (finalLocation > GRID_SIZE) { // end position is off the bottom
		System.out.println("location = " + location + ", startupSize = " + startupSize);
		return false;
		}
		return true;
		return finalLocation < GRID_SIZE; // check end position doesn't go off the bottom of the grid
		}

		private Alignment calculateIncrement() {

src/test/java/ch6/GameHelperTest.java

+62 −0

Changes for src/test/java/ch6/GameHelperTest.java: 62 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		@@ -66,6 +66,68 @@ class GameHelperTest {
		assertFalse(gameHelper.verticalStartupFits(47, 3));
		}

		@Test
		void shouldBeAbleToPlaceHorizontalIntoEmptyGridStartingFromValidLocation() {
		// given
		GameHelper gameHelper = new GameHelper();

		// when
		int[] startupCoords = new int[3];
		boolean success = gameHelper.bruteForcePlace(3, startupCoords, 1, 0);

		// then
		assertTrue(success);
		assertArrayEquals(new int[]{0, 1, 2}, startupCoords);
		}

		@Test
		void shouldBeAbleToPlaceVerticalIntoEmptyGridStartingFromValidLocation() {
		// given
		GameHelper gameHelper = new GameHelper();

		// when
		int[] startupCoords = new int[3];
		boolean success = gameHelper.bruteForcePlace(3, startupCoords, 7, 0);

		// then
		assertTrue(success);
		assertArrayEquals(new int[]{0, 7, 14}, startupCoords);
		}

		@Test
		void shouldNotBeAbleToPlaceHorizontalIntoGridAtSameLocationAsExisting() {
		// given
		GameHelper gameHelper = new GameHelper();
		boolean setupSuccess = gameHelper.bruteForcePlace(3, new int[3], 1, 8); // "B1"
		assertTrue(setupSuccess);
		System.out.println(gameHelper);

		// when
		int[] startupCoords = new int[3];
		boolean success = gameHelper.bruteForcePlace(3, startupCoords, 1, 9); // "C1" - horizontal
		System.out.println(gameHelper);

		// then
		assertFalse(success);
		}

		@Test
		void shouldNotBeAbleToPlaceVerticalIntoGridAtSameLocationAsExisting() {
		// given
		GameHelper gameHelper = new GameHelper();
		boolean setupSuccess = gameHelper.bruteForcePlace(3, new int[3], 1, 8); // "B1"
		assertTrue(setupSuccess);
		System.out.println(gameHelper);

		// when
		int[] startupCoords = new int[3];
		boolean success = gameHelper.bruteForcePlace(3, startupCoords, 7, 1); // "A1" - vertical
		System.out.println(gameHelper);

		// then
		assertFalse(success);
		}

		@Test
		void shouldTurnIndexIntoAlphaCoords() {
		GameHelper gameHelper = new GameHelper();