JAVA 小抄 -000- 初始

 /**
     * 把List里面的对象的某个属性提取出来
     */
    public static <T, R> List<R> toList(Collection<T> list, Function<T, R> function) {
        return toCollection(list, function, ArrayList::new);
    }
    
    /**
     * 把List里面的对象的某个属性提取出来
     */
    public static <T, R> List<R> toList(Stream<T> list, Function<T, R> function) {
        return toCollection(list, function, ArrayList::new);
    }
 
 /**
     * 把List里面的对象的某个属性提取出来
     */
    public static <T, R, C extends Collection<R>> C toCollection(Collection<T> list, Function<T, R> function, Supplier<C> collectionFactory) {
        if (CollectionUtils.isEmpty(list)) {
            return collectionFactory.get();
        }
        return toCollection(list.stream(), function, collectionFactory);
    }

    /**
     * 把stream里面的对象的某个属性提取出来
     */
    public static <T, R, C extends Collection<R>> C toCollection(Stream<T> stream, Function<T, R> function, Supplier<C> collectionFactory) {
        return stream.collect(Collectors.mapping(function, Collectors.toCollection(collectionFactory)));
    }