关于Lambda表达式的方法引用和构造器引用简的单示例

@FunctionalInterface
interface Instance<E>{
	E get(String name, int age);
}

@FunctionalInterface
interface Converter{
	Integer converter(String age);
}

@FunctionalInterface
interface Say{
	String say(Dog dog, String hobby);
}

class Dog{
	private String name;
	private int age;
	
	public Dog(String name, int age) {
		this.name = name;
		this.age = age;
	}
	
	public String getName() {
		return name;
	}
	
	public void grow(Converter con, String age) {
		this.age = con.converter(age);
	}
	
	public int getNameLength(String name) {
		return name.length();
	}
	
	public String hobby(String hobby) {
		return this.toString()+" I love "+hobby;
	}

	@Override
	public String toString() {
		return "Dog [name=" + name + ", age=" + age + "]";
	}
}

public class Client {
	public static void main(String[] args) {
		//使用方法引用和构造器引用使得 Lambda 表达式更加简洁
		
		//Instance<Dog> instance1 = (name, age)->new Dog(name,age);
		Instance<Dog> instance = Dog::new;
		Dog dog = instance.get("小黑", 12);
		String str = dog.toString();
		System.out.println(str);
		
		
		//Converter converter1 = age->Integer.valueOf(age);
		Converter converter1 = Integer::valueOf;
		dog.grow(converter1,"18");
		System.out.println(dog.toString());
		
		
		//Converter converter2 = name->dog.getNameLength(name);	
		Converter converter2 = dog::getNameLength;
		int len = converter2.converter(dog.getName());
		System.out.println("dog 的名字有："+len+" 个字符!");
		
		
		//Say say1 = (dog1,hobby)->dog1.hobby(hobby);
		Say dogSay = Dog::hobby;
		String str1 = dogSay.say(dog, "running！");
		System.out.println(str1);
	}
}

public class Dog implements Comparable<Dog>{
	private String name;
	private int age;
	
	public Dog(String name, int age) {
		this.name = name;
		this.age = age;
	}
	
	public int getAge() {
		return age;
	}
	
	@Override
	public int compareTo(Dog dog) {
		return this.age > dog.age ? 1 : this.age < dog.age ? -1 : 0;
	}
	
	@Override
	public String toString() {
		return "Dog [name=" + name + ", age=" + age + "]";
	}
}

public class ClientTest {
	public static void main(String[] args) {
		LinkedList<Dog> list = new LinkedList<>();
		list.add(new Dog("大黄",12));
		list.add(new Dog("小黑",13));
		list.add(new Dog("二哈",11));
		list.add(new Dog("小白",9));
		list.add(new Dog("旺财",8));
		
		//引用特定对象的实例方法
		Consumer<Dog> consumer = System.out::println;  
		list.forEach(consumer);    
		
		System.out.println("-------模拟上面的 foreach 方法-----------");
		Consumer<Dog> con = dog->System.out.println(dog);
		for (Dog dog : list ) {
			con.accept(dog);
		}
	}
}