Java Vector isEmpty()用法及代码示例

Java中的Java.util.Vector.isEmpty()方法用于检查和验证Vector是否为空。如果Vector为空，则返回True，否则返回False。

用法:

Vector.isEmpty()

参数：此方法不带任何参数。

返回值：如果Vector为空，则此函数返回True，否则返回False。

以下示例程序旨在说明Java.util.Vector.isEmpty()方法：

示例1:

// Java code to illustrate isEmpty() 
import java.util.*; 
  
public class VectorDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty Vector 
        Vector<String> vec_tor = new Vector<String>(); 
  
        // Use add() method to add elements into the Vector 
        vec_tor.add("Welcome"); 
        vec_tor.add("To"); 
        vec_tor.add("Geeks"); 
        vec_tor.add("4"); 
        vec_tor.add("Geeks"); 
  
        // Displaying the Vector 
        System.out.println("Vector:  " + vec_tor); 
  
        // Verifying if the Vector is empty or not 
        System.out.println("Is the Vector empty? "
                           + vec_tor.isEmpty()); 
  
        // Clearing the Vector 
        vec_tor.clear(); 
  
        // Displaying the Vector 
        System.out.println("Vector after clear(): "
                           + vec_tor); 
  
        // Verifying if the Vector is empty or not 
        System.out.println("Is the Vector empty? "
                           + vec_tor.isEmpty()); 
    } 
}

输出：

Vector:  [Welcome, To, Geeks, 4, Geeks]
Is the Vector empty? false
Vector after clear(): []
Is the Vector empty? true

示例2:

// Java code to illustrate isEmpty() 
import java.util.*; 
  
public class VectorDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty Vector 
        Vector<Integer> vec_tor = new Vector<Integer>(); 
  
        // Displaying the Vector 
        System.out.println("Vector:  " + vec_tor); 
  
        // Verifying if the Vector is empty or not 
        System.out.println("Is the Vector empty? "
                           + vec_tor.isEmpty()); 
    } 
}

输出：

Vector:  []
Is the Vector empty? true

相关用法

注：本文由纯净天空筛选整理自kundankumarjha大神的英文原创作品 Vector isEmpty() Method in Java。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。