ObservableMergers.java 文件源码

@SafeVarargs
public static <K, V, W> void mergeMap(Function<? super W, ? extends V> mapper,
    ObservableMap<K, V> into, ObservableMap<K, W>... maps) {
    final ObservableMap<K, V> map = into;
    for (ObservableMap<K, W> m : maps) {
        for (Entry<K, W> entry : m.entrySet()) {
            map.put(entry.getKey(), mapper.apply(entry.getValue()));
        }
        m.addListener((MapChangeListener<K, W>) c -> {
            if (c.wasAdded()) {
                map.put(c.getKey(), mapper.apply(c.getValueAdded()));
            }
            if (c.wasRemoved()) {
                map.remove(c.getKey());
            }
        });
    }
}