JAVA8新特性---函数式接口

@FunctionalInterface
public interface Runnable {
    /**
     * When an object implementing interface <code>Runnable</code> is used
     * to create a thread, starting the thread causes the object‘s
     * <code>run</code> method to be called in that separately executing
     * thread.
     * <p>
     * The general contract of the method <code>run</code> is that it may
     * take any action whatsoever.
     *
     * @see     java.lang.Thread#run()
     */
    public abstract void run();
}

@FunctionalInterface
public interface Comparator<T> {
    /**
     *
     * @param o1 the first object to be compared.
     * @param o2 the second object to be compared.
     * @return a negative integer, zero, or a positive integer as the
     *         first argument is less than, equal to, or greater than the
     *         second.
     * @throws NullPointerException if an argument is null and this
     *         comparator does not permit null arguments
     * @throws ClassCastException if the arguments‘ types prevent them from
     *         being compared by this comparator.
     */
    int compare(T o1, T o2);

@FunctionalInterface
public interface MyNumber<T> {

public boolean compare(Integer a,Integer b);   
}

@Test
public void test2(){

   MyNumber<Integer> myNumber = (Integer a,Integer b) -> a>b;

   System.out.println(myNumber.compare(1,2));
}

@Test
    public void test() {
        System.out.println(studytime(()->"studyTime"));

    }
    //供给型函数，无参有返回值
    public String studytime(Supplier<String> supplier){
       return supplier.get();
    }

 @Test
    public void test2(){
        String goodOneDay = goodDay("goodOneDay", (s -> s));
        System.out.println(goodOneDay);

    }
    public String goodDay(String s, Function<String,String> function){

        return function.apply(s);
    }

@Test
    public void test3(){
        List<String> list = Arrays.asList("杏鲍菇","金针菇","大枣","平菇");
        List<String> filterList = new ArrayList<>();
        list.forEach((s)-> {
           if(s.contains("菇")) {
               filterList.add(s);
           }
        });
        System.out.println("filterList:"+filterList);

    }