oppgave: highscorelist

src/main/java/oving6/highscorelist/HighscoreList.java

@@ -0,0 +1,79 @@
+package oving6.highscorelist;
+
+import java.util.List;
+import java.util.ArrayList;
+import java.util.Collections;
+
+public class HighscoreList {
+	private int maxSize = 0;
+	private List<Integer> results = new ArrayList<Integer>();
+	private ArrayList<HighscoreListListener> highscoreListListeners = new ArrayList<HighscoreListListener>();
+
+	HighscoreList(int maxSize) {
+		this.maxSize = maxSize;
+	}
+
+	public int size() {
+		return results.size();
+	}
+
+	public int getElement(int i) {
+		if (i < 0 || i >= results.size()) {
+			throw new IllegalArgumentException("Invalid value for i");
+		}
+		return results.get(i);
+	}
+
+	public void addResult(int r) {
+		if (maxSize <= 0) {
+			return;
+		}
+
+		int idx = results.size();
+
+		for (int i = 0; i < results.size(); i++) {
+			if (r < results.get(i)) {
+				idx = i;
+				break;
+			}
+		}
+
+		if (results.size() < maxSize || idx < results.size()) {
+			results.add(r);
+			Collections.sort(results);
+			while (results.size() > maxSize) {
+			    results.removeLast();
+			}
+			sendHighscoreEvent(idx);
+		}
+
+	}
+
+	public void addHighscoreListListener(HighscoreListListener listener) {
+		highscoreListListeners.add(listener);
+
+	}
+
+	public void removeHighscoreListListener(HighscoreListListener listener) {
+		highscoreListListeners.remove(listener);
+	}
+
+	private void sendHighscoreEvent(int i) {
+		for (HighscoreListListener listener : highscoreListListeners) {
+			listener.listChanged(this, i);
+		}
+	}
+
+	@Override
+	public String toString() {
+		String s = "[";
+		for (int i = 0; i < results.size(); i++) {
+			s += results.get(i);
+			if (i < results.size() - 1) {
+				s += ",";
+			}
+		}
+		s += "]";
+		return s;
+	}
+}

src/main/java/oving6/highscorelist/HighscoreListListener.java

@@ -0,0 +1,5 @@
+package oving6.highscorelist;
+
+public interface HighscoreListListener {
+	void listChanged(HighscoreList l, int i);
+}

src/main/java/oving6/highscorelist/HighscoreProgram.java

@@ -0,0 +1,35 @@
+package oving6.highscorelist;
+
+import java.util.Scanner;
+
+public class HighscoreProgram implements HighscoreListListener {
+	HighscoreList highscoreList;
+
+	void main() {
+		init();
+		run();
+	}
+
+	void init() {
+		highscoreList = new HighscoreList(10);
+		highscoreList.addHighscoreListListener(this);
+	}
+
+	void run() {
+		System.out.println("Starting listener:");
+		Scanner scanner = new Scanner(System.in);
+		while (true) {
+			if (scanner.hasNextInt()) {
+				highscoreList.addResult(scanner.nextInt());
+			} else {
+				scanner.next();
+			}
+		}
+	}
+
+	@Override
+	public void listChanged(HighscoreList l, int i) {
+		System.out.println("List[" + i + "]: " + l.toString());
+	}
+
+}