Made OsuGroupList a singleton.

(This makes a lot more sense than storing the single pointer in Opsu.groups.)

Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>

src/itdelatrisu/opsu/Opsu.java

@@ -54,11 +54,6 @@ import org.newdawn.slick.util.ResourceLoader;
  * Creates game container, adds all other states, and initializes song data.
  */
 public class Opsu extends StateBasedGame {
-	/**
-	 * Song group structure (each group contains of an ArrayList of OsuFiles).
-	 */
-	public static OsuGroupList groups = new OsuGroupList();
-
 	/**
 	 * Game states.
 	 */
@@ -93,6 +88,9 @@ public class Opsu extends StateBasedGame {
 		addState(new Options(STATE_OPTIONS));
 	}
 
+	/**
+	 * Launches opsu!.
+	 */
 	public static void main(String[] args) {
 		// log all errors to a file
 		Log.setVerbose(false);

src/itdelatrisu/opsu/OsuGroupList.java

@@ -30,6 +30,11 @@ import java.util.regex.Pattern;
  * Indexed, expanding, doubly-linked list data type for song groups.
  */
 public class OsuGroupList {
+	/**
+	 * Song group structure (each group contains of an ArrayList of OsuFiles).
+	 */
+	private static OsuGroupList list = new OsuGroupList();
+
 	/**
 	 * Search pattern for conditional expressions.
 	 */
@@ -63,11 +68,16 @@ public class OsuGroupList {
 	 * The last search query.
 	 */
 	private String lastQuery = "";
+
+	/**
+	 * Returns the single instance of this class.
+	 */
+	public static OsuGroupList get() { return list; }
 	
 	/**
 	 * Constructor.
 	 */
-	public OsuGroupList() {
+	private OsuGroupList() {
 		parsedNodes = new ArrayList<OsuGroupNode>();
 		nodes = parsedNodes;
 	}

src/itdelatrisu/opsu/OsuParser.java

@@ -93,7 +93,7 @@ public class OsuParser {
 			}
 			if (!osuFiles.isEmpty()) {  // add entry if non-empty
 				Collections.sort(osuFiles);
-				Opsu.groups.addSongGroup(osuFiles);
+				OsuGroupList.get().addSongGroup(osuFiles);
 			}
 		}
 

src/itdelatrisu/opsu/states/MainMenu.java

@@ -22,6 +22,7 @@ import itdelatrisu.opsu.GameImage;
 import itdelatrisu.opsu.MenuButton;
 import itdelatrisu.opsu.Opsu;
 import itdelatrisu.opsu.OsuFile;
+import itdelatrisu.opsu.OsuGroupList;
 import itdelatrisu.opsu.OsuGroupNode;
 import itdelatrisu.opsu.Utils;
 import itdelatrisu.opsu.audio.MusicController;
@@ -217,7 +218,7 @@ public class MainMenu extends BasicGameState {
 		g.setFont(Utils.FONT_MEDIUM);
 		int lineHeight = Utils.FONT_MEDIUM.getLineHeight();
 		g.drawString(String.format("Loaded %d songs and %d beatmaps.",
-				Opsu.groups.size(), Opsu.groups.getMapCount()), 25, 25);
+				OsuGroupList.get().size(), OsuGroupList.get().getMapCount()), 25, 25);
 		if (MusicController.isTrackLoading())
 			g.drawString("Track loading...", 25, 25 + lineHeight);
 		else if (MusicController.trackExists()) {
@@ -349,7 +350,7 @@ public class MainMenu extends BasicGameState {
 		} else if (musicNext.contains(x, y)) {
 			boolean isTheme = MusicController.isThemePlaying();
 			SongMenu menu = (SongMenu) game.getState(Opsu.STATE_SONGMENU);
-			OsuGroupNode node = menu.setFocus(Opsu.groups.getRandomNode(), -1, true);
+			OsuGroupNode node = menu.setFocus(OsuGroupList.get().getRandomNode(), -1, true);
 			boolean sameAudio = false;
 			if (node != null) {
 				sameAudio = MusicController.getOsuFile().audioFilename.equals(node.osuFiles.get(0).audioFilename);
@@ -361,7 +362,7 @@ public class MainMenu extends BasicGameState {
 		} else if (musicPrevious.contains(x, y)) {
 			if (!previous.isEmpty()) {
 				SongMenu menu = (SongMenu) game.getState(Opsu.STATE_SONGMENU);
-				menu.setFocus(Opsu.groups.getBaseNode(previous.pop()), -1, true);
+				menu.setFocus(OsuGroupList.get().getBaseNode(previous.pop()), -1, true);
 				if (Options.isDynamicBackgroundEnabled())
 					bgAlpha = 0f;
 			} else

src/itdelatrisu/opsu/states/SongMenu.java

@@ -22,6 +22,7 @@ import itdelatrisu.opsu.GameImage;
 import itdelatrisu.opsu.MenuButton;
 import itdelatrisu.opsu.Opsu;
 import itdelatrisu.opsu.OsuFile;
+import itdelatrisu.opsu.OsuGroupList;
 import itdelatrisu.opsu.OsuGroupNode;
 import itdelatrisu.opsu.OsuParser;
 import itdelatrisu.opsu.SongSort;
@@ -287,7 +288,7 @@ public class SongMenu extends BasicGameState {
 			g.setColor(Utils.COLOR_BLACK_ALPHA);
 			g.fillRoundRect(width - 10, scrollStartY, 5, scrollEndY, 4);
 			g.setColor(Color.white);
-			g.fillRoundRect(width - 10, scrollStartY + (scrollEndY * startNode.index / Opsu.groups.size()), 5, 20, 4);
+			g.fillRoundRect(width - 10, scrollStartY + (scrollEndY * startNode.index / OsuGroupList.get().size()), 5, 20, 4);
 		}
 
 		// back button
@@ -313,30 +314,30 @@ public class SongMenu extends BasicGameState {
 
 			// store the start/focus nodes
 			if (focusNode != null) {
-				oldFocusNode = Opsu.groups.getBaseNode(focusNode.index);
+				oldFocusNode = OsuGroupList.get().getBaseNode(focusNode.index);
 				oldFileIndex = focusNode.osuFileIndex;
 			}
 
-			if (Opsu.groups.search(search.getText())) {
+			if (OsuGroupList.get().search(search.getText())) {
 				// empty search
 				if (search.getText().isEmpty())
 					searchResultString = "Type to search!";
 
 				// search produced new list: re-initialize it
 				startNode = focusNode = null;
-				if (Opsu.groups.size() > 0) {
+				if (OsuGroupList.get().size() > 0) {
-					Opsu.groups.init();
+					OsuGroupList.get().init();
 					if (search.getText().isEmpty()) {  // cleared search
 						// use previous start/focus if possible
 						if (oldFocusNode != null)
 							setFocus(oldFocusNode, oldFileIndex, true);
 						else
-							setFocus(Opsu.groups.getRandomNode(), -1, true);
+							setFocus(OsuGroupList.get().getRandomNode(), -1, true);
 					} else {
-						int size = Opsu.groups.size();
+						int size = OsuGroupList.get().size();
 						searchResultString = String.format("%d match%s found!",
 								size, (size == 1) ? "" : "es");
-						setFocus(Opsu.groups.getRandomNode(), -1, true);
+						setFocus(OsuGroupList.get().getRandomNode(), -1, true);
 					}
 					oldFocusNode = null;
 					oldFileIndex = -1;
@@ -362,7 +363,7 @@ public class SongMenu extends BasicGameState {
 		OsuGroupNode node = startNode;
 		boolean isHover = false;
 		for (int i = 0; i < MAX_BUTTONS && node != null; i++, node = node.next) {
-			float cx = (node.index == Opsu.groups.getExpandedIndex()) ? buttonX * 0.9f : buttonX;
+			float cx = (node.index == OsuGroupList.get().getExpandedIndex()) ? buttonX * 0.9f : buttonX;
 			if ((mouseX > cx && mouseX < cx + buttonWidth) &&
 				(mouseY > buttonY + (i * buttonOffset) && mouseY < buttonY + (i * buttonOffset) + buttonHeight)) {
 				if (i == hoverIndex) {
@@ -418,10 +419,10 @@ public class SongMenu extends BasicGameState {
 				if (sort != SongSort.getSort()) {
 					SongSort.setSort(sort);
 					SoundController.playSound(SoundEffect.MENUCLICK);
-					OsuGroupNode oldFocusBase = Opsu.groups.getBaseNode(focusNode.index);
+					OsuGroupNode oldFocusBase = OsuGroupList.get().getBaseNode(focusNode.index);
 					int oldFocusFileIndex = focusNode.osuFileIndex;
 					focusNode = null;
-					Opsu.groups.init();
+					OsuGroupList.get().init();
 					setFocus(oldFocusBase, oldFocusFileIndex, true);
 				}
 				return;
@@ -429,7 +430,7 @@ public class SongMenu extends BasicGameState {
 		}
 
 		// song buttons
-		int expandedIndex = Opsu.groups.getExpandedIndex();
+		int expandedIndex = OsuGroupList.get().getExpandedIndex();
 		OsuGroupNode node = startNode;
 		for (int i = 0; i < MAX_BUTTONS && node != null; i++, node = node.next) {
 			// is button at this index clicked?
@@ -484,7 +485,7 @@ public class SongMenu extends BasicGameState {
 			game.enterState(Opsu.STATE_OPTIONS, new EmptyTransition(), new FadeInTransition(Color.black));
 			break;
 		case Input.KEY_F2:
-			setFocus(Opsu.groups.getRandomNode(), -1, true);
+			setFocus(OsuGroupList.get().getRandomNode(), -1, true);
 			break;
 		case Input.KEY_F12:
 			Utils.takeScreenShot();
@@ -598,7 +599,7 @@ public class SongMenu extends BasicGameState {
 				n++;
 				shifted = true;
 			} else if (n > 0 && startNode.next != null &&
-			           Opsu.groups.getNode(startNode, MAX_BUTTONS) != null) {
+			           OsuGroupList.get().getNode(startNode, MAX_BUTTONS) != null) {
 				startNode = startNode.next;
 				buttonY -= buttonOffset / 4;
 				if (buttonY < height * 0.14f)
@@ -632,9 +633,9 @@ public class SongMenu extends BasicGameState {
 		OsuGroupNode oldFocus = focusNode;
 
 		// expand node before focusing it
-		int expandedIndex = Opsu.groups.getExpandedIndex();
+		int expandedIndex = OsuGroupList.get().getExpandedIndex();
 		if (node.index != expandedIndex) {
-			node = Opsu.groups.expand(node.index);
+			node = OsuGroupList.get().expand(node.index);
 
 			// if start node was previously expanded, move it
 			if (startNode != null && startNode.index == expandedIndex)
@@ -649,13 +650,13 @@ public class SongMenu extends BasicGameState {
 		// change the focus node
 		if (flag || (startNode.index == 0 && startNode.osuFileIndex == -1 && startNode.prev == null))
 			startNode = node;
-		focusNode = Opsu.groups.getNode(node, pos);
+		focusNode = OsuGroupList.get().getNode(node, pos);
 		OsuFile osu = focusNode.osuFiles.get(focusNode.osuFileIndex);
 		MusicController.play(osu, true);
 		Utils.loadGlyphs(osu);
 
 		// check startNode bounds
-		while (startNode.index >= Opsu.groups.size() + length - MAX_BUTTONS && startNode.prev != null)
+		while (startNode.index >= OsuGroupList.get().size() + length - MAX_BUTTONS && startNode.prev != null)
 			startNode = startNode.prev;
 
 		// make sure focusNode is on the screen (TODO: cleanup...)

src/itdelatrisu/opsu/states/Splash.java

@@ -20,6 +20,7 @@ package itdelatrisu.opsu.states;
 
 import itdelatrisu.opsu.GameImage;
 import itdelatrisu.opsu.Opsu;
+import itdelatrisu.opsu.OsuGroupList;
 import itdelatrisu.opsu.OsuParser;
 import itdelatrisu.opsu.OszUnpacker;
 import itdelatrisu.opsu.Utils;
@@ -133,8 +134,8 @@ public class Splash extends BasicGameState {
 		// change states when loading complete
 		if (finished && alpha >= 1f) {
 			// initialize song list
-			Opsu.groups.init();
+			OsuGroupList.get().init();
-			((SongMenu) game.getState(Opsu.STATE_SONGMENU)).setFocus(Opsu.groups.getRandomNode(), -1, true);
+			((SongMenu) game.getState(Opsu.STATE_SONGMENU)).setFocus(OsuGroupList.get().getRandomNode(), -1, true);
 
 			// play the theme song
 			if (Options.isThemSongEnabled())