java.util.Vector.insertElementAt(E obj,int index) 方法示例 Java.util.Observable.deleteObservers() 方法 java.util.Vector.isEmpty() 方法示例 java.util.Vector.insertElementAt(E obj,int index) 方法示例 package com.codingdict; import java.util.Vector; public class VectorDemo { public static void main(String[] args) { // create an empty Vector vec with an initial capacity of 4 Vector<Integer> vec = new Vector<Integer>(4); // use add() method to add elements in the vector vec.add(4); vec.add(3); vec.add(2); vec.add(1); // let us print all the elements available in vector System.out.println("Added numbers are :- "); for (Integer number : vec) { System.out.println("Number = " + number); } // let us insert element at 1st position vec.insertElementAt(133, 1); System.out.println("Added numbers after insertion :- "); // let us print the elements for (Integer number : vec) { System.out.println("Number = " + number); } } } Java.util.Observable.deleteObservers() 方法 java.util.Vector.isEmpty() 方法示例