Java Vector lastElement()
Java Vector类的
lastElement()方法用于获取Vector 的最后一个分量。
语法
以下是
lastElement()方法的声明:
参数
此方法不接受任何参数。
返回
lastElement()方法返回向量的最后一个元素，即位于索引size()-1处的分量。
异常
NoSuchElementException -如果向量为空，则此方法引发异常。
兼容版本
Java 1.2及更高版本
示例1
//Program to illustrate the lastElement() method
import java.util.*;
public class VectorLastElementExample1 {
public static void main(String arg[]) {
//Create an empty vector
Vector<String> vec = new Vector<>(4);
//Add elements in the vector
vec.add("Java");
vec.add("JavaScript");
vec.add("Android");
vec.add("Python");
//Obtain the last element of this vector
System.out.println("The last element of a vector is: " +vec.lastElement());
}
}
输出:
The last element of a vector is: Python
示例2
//Program to illustrate the lastElement() method
import java.util.*;
public class VectorLastElementExample2 {
public static void main(String arg[]) {
//Create an empty vector
Vector<Integer> vectorObject = new Vector<Integer>(4);
//Add elements to the vector
vectorObject.add(11);
vectorObject.add(22);
vectorObject.add(33);
vectorObject.add(44);
//Displaying the vector list
System.out.println("Element of a vector is: " +vectorObject);
//Obtain the last element of this vector
System.out.println("The last element of a vector is: " +vectorObject.lastElement());
}
}
输出:
Element of a vector is: [11, 22, 33, 44]
The last element of a vector is: 44
示例3
//Program to illustrate the lastElement() method
import java.util.*;
public class VectorLastElementExample3 {
public static void main(String arg[]) {
//Create an empty vector
Vector<Integer> vecObj = new Vector<Integer>(4);
//Add elements to the vector
vecObj.add(101);
vecObj.add(202);
vecObj.add(303);
vecObj.add(404);
//Obtain the last element of this vector
System.out.println("Last element of vector is: " +vecObj.lastElement());
//Use clear() method to remove all element of this vector
vecObj.clear();
//Again obtain the last element of this vector after clear method
System.out.println("The last element of a vector is: " +vecObj.lastElement());
}
}
输出:
The last element of a vector is: 404
Exception in thread "main" java.util.NoSuchElementException
at java.base/java.util.Vector.lastElement(Vector.java:525)
at myPackage.VectorLastElementExample3.main(VectorLastElementExample3.java:17)
