ip-ch05-example-04.java

public MapRecipe(Map<?, ?> map) {
    if (map == null) throw new NullPointerException("map is null");
    entries = new ArrayList<Object[]>(map.size());
    if (RecipeHelper.hasDefaultConstructor(map.getClass())) {
        this.typeClass = map.getClass();
    } else if (map instanceof SortedMap) {
        this.typeClass = TreeMap.class;
    } else if (map instanceof ConcurrentMap) {
        this.typeClass = ConcurrentHashMap.class;
    } else {
        this.typeClass = LinkedHashMap.class;
    }
    putAll(map);
}