初试java8

排序以及“：：”的方法调用

import java.util.LinkedList;
import java.util.List;
import java.util.Comparator;
class fruit{
	String name;
	int weight;
	public fruit(String name,int weight) {
		// TODO Auto-generated constructor stub
		this.name = name;
		this.weight = weight;
	}
	public int getweight() {
		return this.weight;
	}
	public String getName() {
		return this.name;
	}
}
public class test {
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		List<fruit> l1 = new LinkedList<fruit>();
		l1.add(new fruit("apple", 15));
		l1.add(new fruit("orange", 15));
		l1.add(new fruit("banan", 15));
		l1.add(new fruit("gargon_furit", 15));
		l1.add(new fruit("pear", 15));
		Comparator<fruit> c = Comparator.comparing(fruit::getweight).reversed();
		l1.sort(c);
		for(int i=0;i<l1.size();i++) {
			System.out.println(l1.get(i).name +"  " + l1.get(i).weight);
		}
	}

}

如上所示，有了Comparetor用法之后特别简单，而且Comparetor提供了“比较器复合”的功能；
比如说排序后的结果如果需要逆序，那就调用reversed方法，还有比较器链，如果水果一样重，还可以接着比较名字，方法是thenComparing();

	Comparator<fruit> c = Comparator.comparing(fruit::getweight).reversed().thenComparing(fruit::getName);

修改之后