按字长排序显示错误

package lambda;

import javax.swing.*;
import java.util.Arrays;
import java.util.Date;


/**

 * Charles建立

 * 2020/2/26

 */
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("字典排序");
        Arrays.sort(planets);
        System.out.println(Arrays.toString(planets));
        System.out.println("字长排序");
        Arrays.sort(planets,(first,second)->first.length()-second.length());
        System.out.println(planets);
        Timer t=new Timer(1000,event-> System.out.println("The time is "+new Date()));
        t.start();
        JOptionPane.showMessageDialog(null, "结束运行？");
        System.exit(0);
    }
}