Java 8 in Action

https://www.cnblogs.com/HelloDeveloper/p/11404523.html

/**
 * @param args
 */
public static void main(String[] args) {
    List<Integer> numberList = Arrays.asList(1, 2, 3);
    System.out.println("原集合:" + numberList);

    List<Integer> numbers = filter(numberList, (Integer i) -> i % 2 == 0);
    System.out.println("能被2整除的数:" + numbers);
}

/**
 * 筛选绿色苹果
 */
public static <T> List<T> filter(List<T> list, Predicate<T> predicate) {
    List<T> resultList = new ArrayList<>();
    for (T t : list) {
        // 谓词对象封装了条件
        if (predicate.filter(t)) {
            resultList.add(t);
        }
    }
    return resultList;
}

/**
 * @param <T>
 */
public interface Predicate<T> {
    boolean filter(T t);
}

numberList.sort((Integer o1, Integer o2)->o1.compareTo(o2));

Thread t1 = new Thread(() -> System.out.println("Hello Lambda!"));

t1.start();