java lambda 表达式

简介

与其说是 lambda 表达式 还不如说是 省略定义 函数名称 的格式
这就叫人话

code

核心
Arrays.sort(planets, (first, second)->first.length() - second.length());

package cn;

import java.util.Arrays;
import java.util.Date;

import javax.swing.JOptionPane;
import javax.swing.Timer;

public class LambdaTest {
	public static void main(String[] args){
		String[] planets = new String[] {
				"Mercury", "Venus", "Earth", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune"
		};
		System.out.println(Arrays.toString(planets));
		System.out.println("Sorted in dictionary order:");
		Arrays.sort(planets);
		System.out.println(Arrays.toString(planets));
		System.out.println("Sorted by length:");
		Arrays.sort(planets, (first, second)->first.length() - second.length());
		System.out.println(Arrays.toString(planets));
		
		Timer t = new Timer(1000, event-> System.out.println("The time is " + new Date()));
		t.start();
		
		JOptionPane.showMessageDialog(null, "Quit program");;
		System.exit(0);
	}
}