vector in java programming Hands on Coding

vector in java

• This is a predefined class and can be used to store the data of different type (float, int, character, string).
• It is defined inside the  java.util package.
• It is same as traditional arrays of Java, except that, it grows as per requirement.
• Elements of vector can be accessed by their index number which starts from zero.
• Vectors are in Synchronized form.
• Vectors implement a dynamic array which means it can grow or shrink as per our requirement.
• It is commonly used when there is no idea about the number of elements in an array.
• There are three different ways to create vector.

               1. Vector vec = new Vector();

• It creates an empty Vector which is of capacity 10.
• The default or initial capacity of vector will be 10.

               2. Vector vec = new Vector(5);

• This creates a Vector of initial capacity of 5.

              3. Vector vec = new Vector(5,10);

• Here 5 is the initial capacity whereas 10 is the capacity of increment.
• It means upon insertion of 6th element the size would be 15 (5+10).

Example

 import java.util.Vector;  
 import java.util.Enumeration;  
  class Program   
  {  
   public static void main(String args[])   
   {  
    /*creating variable of enumeration*/  
    Enumeration courses;  
    /*creating object of vector*/  
    Vector courseName = new Vector();   
    /*adding data into vector*/  
    courseName.add("C");  
    courseName.add("C++");  
    courseName.add("JAVA");  
    courseName.add("PHP");  
    courseName.add("ANDROID");  
    courseName.add("C#");  
    /*passing vector data into enumeration*/  
    courses = courseName.elements();  
    /*Accessing data of enumeration*/  
    while (courses.hasMoreElements())   
    {  
     /*printing data of enumeration*/  
     System.out.println(courses.nextElement());   
    }  
   }  
 }  
 /*  
 Output  
 C  
 C++  
 JAVA  
 PHP  
 ANDROID  
 C#  
 */