Win a copy of Hands On Software Engineering with Python this week in the Jython/Python forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
  • Campbell Ritchie
  • Jeanne Boyarsky
  • Bear Bibeault
  • Knute Snortum
  • Liutauras Vilda
  • Tim Cooke
  • Devaka Cooray
  • Paul Clapham
Saloon Keepers:
  • Tim Moores
  • Frits Walraven
  • Ron McLeod
  • Ganesh Patekar
  • salvin francis
  • Tim Holloway
  • Carey Brown
  • Stephan van Hulst

some queries in the program  RSS feed

Ranch Hand
Posts: 127
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
hi all,
consider the following program:
import java.util.*;
public class VecNum
public static void main(String argv[])
Vector v = new Vector();
v.add(new Integer(1));
v.add(new Integer(2));
for(int i=0; i < v.size();i ++)//line1
Integer iw =(Integer) v.get(i);//line2



In the above program i have some queries:
1.why we need to use vector for wrapping all the integer values
2.what is the purpose of using line1,line2,line3
3.when i compile this program its generating errors

Posts: 10
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

1. You're not using a Vector to wrap your integer values, you're using the Integer Wrapper class. This turns your int primitives into Objects so they can be added to the collection.

2. Lines 1, 2 and 3 retrieve the Integer objects from the Vector. Vector.size() returns the number of components in the Vector and get() retrieves the objects using their index (just like an array).

3. The code compiles and runs fine for me.

Hope this helps!

SCJP 1.4
You guys wanna see my fabulous new place? Or do you wanna look at this tiny ad?
RavenDB is an Open Source NoSQL Database that’s fully transactional (ACID) across your database
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!