an attempt at emulating algebraic data types in Java

HistoryADT.java

import java.util.List;

class HistoryEvent {
    private final HistoryEventItem item;
    private static class HistoryEventItem {
    }
    private static final class WordPlayedItem extends HistoryEventItem {
        private final int player;
        private final List<String> wordsFormed;
        public WordPlayedItem(int player, List<String> wordsFormed) {
            this.player = player;
            this.wordsFormed = wordsFormed;
        }
    }
    private static final class ChallengedItem extends HistoryEventItem {
        private final int player;
        private final boolean successful;
        public ChallengedItem(int player, boolean successful) {
            this.player = player;
            this.successful = successful;
        }
    }
    private static final class PassedItem extends HistoryEventItem {
        private final int player;
        public PassedItem(int player) {
            this.player = player;
        }
    }
    private HistoryEvent(HistoryEventItem item) {
        this.item = item;
    }
    public static HistoryEvent wordPlayed(int player, List<String> wordsFormed) {
        return new HistoryEvent(new WordPlayedItem(player, wordsFormed));
    }
    public static HistoryEvent challenged(int player, boolean successful) {
        return new HistoryEvent(new ChallengedItem(player, successful));
    }
    public static HistoryEvent passed(int player) {
        return new HistoryEvent(new PassedItem(player));
    }
    public <R> R apply(HistoryEventConsumer<R> dispatcher) {
        if (item instanceof WordPlayedItem) {
            final WordPlayedItem data = (WordPlayedItem) item;
            return dispatcher.onPlayWord(data.player, data.wordsFormed);
        }
        if (item instanceof ChallengedItem) {
            final ChallengedItem data = (ChallengedItem) item;
            return dispatcher.onChallenge(data.player, data.successful);
        }
        if (item instanceof PassedItem) {
            final PassedItem data = (PassedItem) item;
            return dispatcher.onPass(data.player);
        }
        throw new AssertionError(item.getClass());
    }
}
interface HistoryEventConsumer<R> {
    public R onPlayWord(int player, List<String> wordsFormed);
    public R onChallenge(int player, boolean successful);
    public R onPass(int player);
}