String, text, numbers, I/O II part

serializable you ignore. 

You have to provide a no argument constructor that reconstructs anything you aren t

going to serialize (for example, opening a new socket). Read about the

Externalizable interface for more details.

Frank LaRosa

 Q: Is it possible to send Vector class in socket communication. If it is, what

function can make it.

Answer: Make sure the objects contained in the Vector are Serializable. Look at

java.io.ObjectOutputStream for serializing the Vector by wrapping the output stream

from socket with the ObjectOutputStream...

Q: How can you tell if an integer is odd or even?

I know an even number is divisible by 2 but I m thinking then how can I detect 

if a resulting number after dividing 2 ints has a remainder?

Answer: Basically the method is simple, if a variable contains an odd number

I want to return the value  zero , and on the other hand if the

variable contains an even number I want to return the value  one .

Check out the % (modulus) operator, it computes the remainder.

public int modMethod(int div){

     if(div%2==0){

         return 1;

    } else{

        return 0;

   }

}

Q: How can I round a number to specified precision?

I have a double field that I would like to round to 2 places of precision, however, it

seems like the documentation on the round function only rounds to

closest integers. So that I would not be able say  .3658585859 = .37 as

I would like.

Answer: can you scale the number up and then down again when you are finished?

e.g.  0.3658585859 * 100 = 36.58585859

round(36.58585859) = 37

37 / 100 = 0.37

 I understand that bitwise operations change the 0/1 bits of a number. Question is

why?

I suppose it s interesting that you can manipulate numbers this way, but I can t think

of a practical use for doing that.

Can anyone help me understand when are bitwise operations used and why you

would use them?

Answer: Bitwise manipulation is often used where memory consumption is critical,

and a piece of information may be encoded in less that one byte, for instance. In

communication software and protocols, information may be interpreted as a stream

of bits where the information is encoded at the bit level, and you use bitwise

file:///F|/a_jsite/350_tips/stings_text__date_numbers_io II.htm (5 of 7) [2001 07 08 11:25:00]