Java ArrayList isEmpty() 方法

示例

检查列表是否为空:

import java.util.ArrayList;

public class Main {
  public static void main(String[] args) {
    ArrayList<String> cars = new ArrayList<String>();
    
    System.out.println(cars.isEmpty());
    
    cars.add("Volvo");
    cars.add("BMW");
    cars.add("Ford");
    cars.add("Mazda");
    
    System.out.println(cars.isEmpty());
  }
}

亲自试一试 »