函数式接口作为方法的返回值

package LambdaTest.LambdaTest04;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;

/**
 * FileName: CompartorDemo
 * Author:   lps
 * Date:     2022/4/5 16:19
 * Sign:刘品水 Q：1944900433
 */
public class CompartorDemo {
    public static void main(String[] args) {
        ArrayList<String> array = new ArrayList<>();
        array.add("aaa");
        array.add("a");
        array.add("bb");
        array.add("c");
        System.out.println("排序前"+array);
        Collections.sort(array);
        System.out.println("排序后"+array);

        Collections.sort(array,getComparator());
        System.out.println("排序后"+array);
        //getComparator(()->);

    }

    private static Comparator<String> getComparator(){
        //匿名内部类
//        Comparator<String> comp=new Comparator<String>() {
//            @Override
//            public int compare(String s1, String s2) {
//                return s1.length()-s2.length();
//            }
//        };
//        return comp;
//        return new Comparator<String>() {
//            @Override
//            public int compare(String s1, String s2) {
//                return s1.length()-s2.length();
//            }
//        };
        //Lambda表达式
//        return (String s1,String s2)->{
//           return s1.length()-s2.length();
//        };
        return (s1,s2)->s1.length()-s2.length();
        //return Comparator.comparingInt(String::length);

    }
}