java.util.ArrayList类的isEmpty()方法用于检查列表是否为空。此方法返回一个布尔值。
public boolean isEmpty()
如果列表为空则返回true，否则返回false。
例
package beginnersbook.com;import java.util.ArrayList;public class IsEmptyExample { public static void main(String args[]) { //ArrayList of Integer Type ArrayList<Integer> al = new ArrayList<Integer>(); //Checking whether the list is empty System.out.println("Is ArrayList Empty: "+al.isEmpty()); //Adding Integer elements al.add(1); al.add(88); al.add(9); al.add(17); //Again checking for isEmpty System.out.println("Is ArrayList Empty: "+al.isEmpty()); //Displaying elements of the list for (Integer num: al) { System.out.println(num); }}}
输出：
Is ArrayList Empty: trueIs ArrayList Empty: false188917
