Need help about Vector class in java

Hello,
I have some questions about Vector class. Please see this short code:
Vector v = new Vector();
v.add(New Integer(5));
Is this the only way to add int value into vector? Performance wise, is this slow? And are there any better and faster way to add/get int element fro vector?
Thank you very much in advance.

Normally (up to Java version 1.4), that's the only way you can add an int to a Vector. The thing is that Vector can only contain Objects, and an int is a primitive, not an object. So you have to wrap the int in an Integer object.
However, Java 5 has a new feature, called autoboxing, which means that the compiler automatically wraps primitive values into objects, so that you can program it like this:
Vector v = new Vector();
v.add(5);Note, this will not make your program faster or more efficient, because the compiler translates this automatically to:
Vector v = new Vector();
v.add(new Integer(5));So in the end, the same bytecode will be produced. Autoboxing is just a feature to make life more convenient for the programmer.

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===============
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Seems like the same question you asked last year.
http://forum.java.sun.com/thread.jspa?threadID=5181153&messageID=9705196#9705196
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// <applet code = "MyClassHW.class" height = 300 width=300> </applet>thank you for your time and help. as always, your efforts are appriciated.

.\Shirt.java:6: invalid method declaration; return type required     public Shirt(int size){
I guess, public Shirt(int size) is constructor in class shirt. You have one int in this constructor. Shirt(int size)
Here you initialize your shirt with two int:
MyClassHW.java:10: cannot resolve symbolsymbol : constructor Shirt (int,int)location: class Shirt          myShirt = new Shirt(1,1);
Shirt(int size, int what?)
It's why it show such message.
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Second and third your classes Shirt and Pants:
public class Shirt extends Object {
int size;
public Shirt(int s) {
size = s;
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return size;
same for Pants, only you need two parameters for it or whatever you want.
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872882 wrote:
Hi All,
Em..i just need some advice about choosing correct career path.I graduated with a first class in IT with business information science in 2009. In 2009 after looking for jobs for few months i took a manager post in a petrol station which i never wanted.(Due to the credit crunch & the Family financial reasons) .Then unfortunately i had to stay out of work for 18months due to a serious spinal code operation i had to face.now in 2011 July im fit & ready to start my life again. but im lost where to start/ which career path to choose. (i've still got the job at the petrol station as the manager)
ive liked data base management subject when i was in the University so, Ive been reading OCA-051 & interested on OCA qualification I just want to know what are the possible jobs i can apply if i get the certification? Basically what should i do to get any IT related job? :( ( i dont like programming)..
Please be kind to reply.
ps:i live in the Uk.
Thanks.You'll sit on your bum and ruin your back again with most IT jobs. With your government shrinking, OCA qualification won't have much worth unless you personally know someone in the private sector that needs help. An operator job with your petrol company (assuming it's not just a mom 'n pop station) would probably require heavy lifting.
IT is a good, solid, growing career path, but most of the work is still programming, and most ways up to better jobs go through that experience. You might be an exception if you have a way to join other skills with your IT education, such as business analysis or sales or web prettyfying. Perhaps the determinants are your personality and goals.
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You try to create an array with line(i) (as far as i see) but you dont need to keep each line in memory. As far as i understand you just need to process lines sequentially.. (Null pointer exception is thrown because you did not create your array properly!)
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http://www.java-tips.org/java-se-tips/java.io/reading-text-from-a-file.html
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http://www.java-tips.org/java-se-tips/java.util/how-to-use-stringtokenizer.html
Then you can just just use length() method of String class:
http://java.sun.com/j2se/1.3/docs/api/java/lang/String.html
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http://java.sun.com/docs/books/tutorial/essential/regex/index.html
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