Java中Lambda表达式和函数式接口的使用和特性

interface MyInterface {
    void doSomething();
}

MyInterface myLambda = () -> System.out.println("Hello, world!");
myLambda.doSomething();

Function<String,Integer> function=(String i)-> Integer.parseInt(i);
System.out.println(function.apply("1")==1);

public static void main(String[] args) {
        Predicate<String> predicate = (s) -> s.length() > 0;
        // 测试字符串的长度是否>0
        System.out.println(predicate.test("hello"));
        // 结果取反
        System.out.println(predicate.negate().test("hello"));
        System.out.println("=====or / and======");
        System.out.println(predicate.test(""));
        // 增加或判断，二者满足其一则为true
        System.out.println(predicate.or(s -> s.equals("")).test(""));
        // 增加与判断，二者都满足则为true
        System.out.println(predicate.and(s -> s.equals("hello")).test(""));
        System.out.println(predicate.and(s -> s.equals("hello")).test("hello"));
        System.out.println("=====isEqual======");
        // 判断是否相等
        System.out.println(Predicate.isEqual("hello").test(""));
        System.out.println(Predicate.isEqual("hello").test("hello"));
        Predicate<Boolean> nonNull = Objects::nonNull;
        Predicate<Boolean> isNull = Objects::isNull;
        Predicate<String> isEmpty = String::isEmpty;
        Predicate<String> isNotEmpty = isEmpty.negate();
    }

public static void main(String[] args) {
   Consumer<Object> consumer1 = new Consumer<Object>() {
   @Override
   public void accept(Object o) {
     System.out.println("这次消费了:" + o.toString());
     }
   };
   consumer1.accept("100w元在双十一！这下穷死了！");
   Consumer<String> consumer2 = s -> System.out.println("这次消费了:" + s);
   consumer2.accept("120w元在双十二！又穷死了！");
}

public static void main(String[] args) {
    // 生成一个字符串
    Supplier<String> supplier1 = () -> "abcde";
    // 生成一个随机数
    Supplier<Integer> supplier2 = () -> new Random().nextInt(10);
    // 产生一个运行时异常
    Supplier<RuntimeException> supplier3 = () -> new RuntimeException();
    System.out.println(supplier1.get());
    System.out.println(supplier2.get().intValue());
    System.out.println(supplier3.get());
}

Function<Integer,Function<Integer,Integer>> functionFunction= x->y->x+y;
System.out.println(functionFunction.apply(2).apply(3));