[Ch6] GameHelper: Tidy up. Formatting comments, removing toString, removing enum. (ed33e3df) · Commits · examples / Head First Java 3rd Edition

src/main/java/ch6/GameHelper.java

+14 −41

Changes for src/main/java/ch6/GameHelper.java: 14 added lines, 41 removed lines.
Original line number	Diff line number	Diff line
		@@ -5,15 +5,15 @@ import java.util.Arrays;
		import java.util.Random;
		import java.util.Scanner;

		import static ch6.GameHelper.Alignment.HORIZONTAL;
		import static ch6.GameHelper.Alignment.VERTICAL;

		public class GameHelper {
		private static final String ALPHABET = "abcdefg";
		private static final int GRID_LENGTH = 7;
		private static final int GRID_SIZE = 49;
		private static final int MAX_ATTEMPTS = 200;

		static final int HORIZONTAL_INCREMENT = 1; // A better way to represent these two things would be an enum
		static final int VERTICAL_INCREMENT = GRID_LENGTH; // (enumeration), which we cover in Appendix B

		private final int[] grid = new int[GRID_SIZE];
		private final Random random = new Random();

		@@ -32,32 +32,31 @@ public class GameHelper {
		boolean success = false; // flag = found a good location ?

		startupCount++; // nth Startup to place
		Alignment alignment = getAlignment(); // alternates between vertical and horizontal
		int increment = getIncrement(); // alternates between vertical and horizontal alignment

		while (!success & attempts++ < MAX_ATTEMPTS) { // main search loop (32)
		int location = random.nextInt(GRID_SIZE); // get random starting point

		for (int i = 0; i < startupCoords.length; i++) { // create an array of proposed co-ordinates for the startup
		startupCoords[i] = location; // put current location in the array
		location += alignment.getIncrement(); // calculate the next location
		location += increment; // calculate the next location
		}
		System.out.println("Trying: " + Arrays.toString(startupCoords));

		if (startupFits(startupCoords, alignment)) { // check the startup would fit on the grid
		if (startupFits(startupCoords, increment)) { // check the startup would fit on the grid
		success = coordsAvailable(startupCoords); // if it fits, check those locations aren't already taken
		} // end loop
		} // end while

		savePositionToGrid(startupCoords); // these coords passed everything, so update the grid with this startup
		savePositionToGrid(startupCoords); // these coords passed all checks, so update the grid with this startup's position
		ArrayList<String> alphaCells = convertCoordsToAlphaFormat(startupCoords);
		System.out.println(alphaCells);
		System.out.println(this);
		return alphaCells;
		}

		boolean startupFits(int[] startupCoords, Alignment alignment) {
		boolean startupFits(int[] startupCoords, int increment) {
		int finalLocation = startupCoords[startupCoords.length - 1];
		if (alignment == HORIZONTAL) {
		if (increment == HORIZONTAL_INCREMENT) {
		return calculateRowFromIndex(startupCoords[0]) == calculateRowFromIndex(finalLocation); // check end is on same row as start
		} else {
		return finalLocation < GRID_SIZE; // check end position doesn't go off the bottom of the grid
		@@ -96,41 +95,15 @@ public class GameHelper {
		return letter + row;
		}

		private Alignment getAlignment() {
		if (startupCount % 2 == 0) { // if EVEN Startup
		return HORIZONTAL; // place horizontally
		} else { // else ODD
		return VERTICAL; // set vertical increment
		}
		}

		private int calculateRowFromIndex(int index) {
		return index / GRID_LENGTH;
		}

		@Override
		public String toString() {
		StringBuilder str = new StringBuilder();
		for (int i = 0; i < grid.length; i++) {
		if (i % 7 == 0) {
		str.append("\n");
		}
		str.append(grid[i]).append(", ");
		}
		return str.toString();
		}

		enum Alignment {
		HORIZONTAL(1), VERTICAL(GRID_LENGTH);

		private final int increment;

		Alignment(int increment) {
		this.increment = increment;
		}

		public int getIncrement() {
		return increment;
		private int getIncrement() {
		if (startupCount % 2 == 0) { // if EVEN Startup
		return HORIZONTAL_INCREMENT; // place horizontally
		} else { // else ODD
		return VERTICAL_INCREMENT; // set vertical increment
		}
		}
		}

src/test/java/ch6/GameHelperTest.java

+3 −5

Changes for src/test/java/ch6/GameHelperTest.java: 3 added lines, 5 removed lines.
Original line number	Diff line number	Diff line
		@@ -2,8 +2,6 @@ package ch6;

		import org.junit.jupiter.api.Test;

		import static ch6.GameHelper.Alignment.HORIZONTAL;
		import static ch6.GameHelper.Alignment.VERTICAL;
		import static org.junit.jupiter.api.Assertions.*;

		class GameHelperTest {
		@@ -47,7 +45,7 @@ class GameHelperTest {
		GameHelper gameHelper = new GameHelper();

		// expect
		assertFalse(gameHelper.startupFits(new int[]{26, 27, 28}, HORIZONTAL));
		assertFalse(gameHelper.startupFits(new int[]{26, 27, 28}, GameHelper.HORIZONTAL_INCREMENT));
		}

		@Test
		@@ -56,7 +54,7 @@ class GameHelperTest {
		GameHelper gameHelper = new GameHelper();

		// expect
		assertTrue(gameHelper.startupFits(new int[]{26, 33, 40}, VERTICAL));
		assertTrue(gameHelper.startupFits(new int[]{26, 33, 40}, GameHelper.VERTICAL_INCREMENT));
		}

		@Test
		@@ -65,7 +63,7 @@ class GameHelperTest {
		GameHelper gameHelper = new GameHelper();

		// expect
		assertFalse(gameHelper.startupFits(new int[]{47, 54, 61}, VERTICAL));
		assertFalse(gameHelper.startupFits(new int[]{47, 54, 61}, GameHelper.VERTICAL_INCREMENT));
		}

		@Test