J2SE 8的Lambda --- Comparator

		Person[] personArray = new Person[]{new Person("Tom"),new Person("Jack"),new Person("Alice")};

		//1. 使用静态的比较器,比较的对象不能为null值

		Arrays.sort(personArray, Comparator.comparing(Person::getName));

		for (Person person : personArray) {

			System.out.println(person.getName());

		}

		System.out.println();

		//2. 使用andThen,在第一层比较相同的情况下，使用andThen的比较器，  多次比较

		personArray = new Person[]{new Person("Tom","A","Tom" ),new Person("Tom","B","Tom" ),new Person("Jack"),new Person("Alice")};

		Arrays.sort(personArray, Comparator.comparing(Person::getName).thenComparing(Person::getFirstName).thenComparing(Person::getLastName));

		for (Person person : personArray) {

			System.out.println(person.getName()+"-"+person.getFirstName()+"-"+person.getLastName());

		}

		System.out.println();

		//3. 变体格式,指定具体比较的内容

		personArray = new Person[]{new Person("Tom"),new Person("Jack"),new Person("Alice")};

		Arrays.sort(personArray, Comparator.comparing(Person::getName, (x,y)->Integer.compare(x.length(), y.length())));

		for (Person person : personArray) {

			System.out.println(person.getName());

		}

		System.out.println();

		//4.对于可能返回null的情况,使用nullsFirst和nullsLast适配器

		personArray = new Person[]{new Person("Tom"),new Person("Jack"),new Person("Alice"),new Person()};

		Arrays.sort(personArray, Comparator.comparing(Person::getName, Comparator.nullsFirst(Comparator.naturalOrder())));

		for (Person person : personArray) {

			System.out.println(person.getName());

		}

		System.out.println();

		//5. 逆序比较 Comparator.comparing().reversed()

		personArray = new Person[]{new Person("Tom"),new Person("Jack"),new Person("Alice"),new Person()};

		Arrays.sort(personArray, Comparator.comparing(Person::getName, Comparator.nullsFirst(Comparator.naturalOrder())).reversed());

		for (Person person : personArray) {

			System.out.println(person.getName());

		}

		System.out.println();
巴特西

J2SE 8的Lambda --- Comparator

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