Programming Forums > Application Development > Java

theguy0000 · Dec 21st, 2005, 11:02 AM

this program was in a tutorial:

import java.io.*;

class PersonalHello {

  public static void main (String args[])
    {
    
      byte name[] = new byte[100];
      int nr_read = 0;

      System.out.println("What is your name?");
      try {
        nr_read = System.in.read(name);
        System.out.print("Hello ");
        System.out.write(name,0,nr_read);
      }
      catch (IOException e) {
        System.out.print("I'm Sorry.  I didn't catch your name.");
      }
      
    }
}

1. what does System.out.write() do?

2. why does it write() "name,0,nr_read" instead of just name? what does nr_read do? what is the 0 there for?

edit: after some experiments, i found that name is a seemingly random strng of characters. I got "[B@10b62c9". nr_read is the number of characters entered plus 2. (when I entered "Matt" nr_read was 6, when I entered "hi" nr_read was 4)

Mjordan2nd · Dec 21st, 2005, 1:17 PM

Name is a random string of characters because an array basically points to the memory address where your array starts. When you System.out.prinln(name) you will get the memory address where name is stored.

For more information on what write() does, check here:
http://java.sun.com/j2se/1.5.0/docs/...intStream.html

theguy0000 · Dec 21st, 2005, 6:22 PM

oh...

then how do i convert the byte to a string and put it in a variable?

titaniumdecoy · Dec 21st, 2005, 7:22 PM

Try

(Toggle Plain Text)

String namestr = new String(name);

Dec 21st, 2005, 11:02 AM	#1
theguy0000 Programmer Join Date: Jul 2005 Posts: 73 Rep Power: 4	I/O question this program was in a tutorial: (Toggle Plain Text) import java.io.; class PersonalHello { public static void main (String args[]) { byte name[] = new byte[100]; int nr_read = 0; System.out.println("What is your name?"); try { nr_read = System.in.read(name); System.out.print("Hello "); System.out.write(name,0,nr_read); } catch (IOException e) { System.out.print("I'm Sorry. I didn't catch your name."); } } } import java.io.; class PersonalHello { public static void main (String args[]) { byte name[] = new byte[100]; int nr_read = 0; System.out.println("What is your name?"); try { nr_read = System.in.read(name); System.out.print("Hello "); System.out.write(name,0,nr_read); } catch (IOException e) { System.out.print("I'm Sorry. I didn't catch your name."); } } } 1. what does System.out.write() do? 2. why does it write() "name,0,nr_read" instead of just name? what does nr_read do? what is the 0 there for? edit: after some experiments, i found that name is a seemingly random strng of characters. I got "[B@10b62c9". nr_read is the number of characters entered plus 2. (when I entered "Matt" nr_read was 6, when I entered "hi" nr_read was 4) Last edited by theguy0000; Dec 21st, 2005 at 11:28 AM.

Dec 21st, 2005, 1:17 PM	#2
Mjordan2nd The Supreme Ruler Join Date: May 2004 Location: Houston Posts: 1,476 Rep Power: 6	Name is a random string of characters because an array basically points to the memory address where your array starts. When you System.out.prinln(name) you will get the memory address where name is stored. For more information on what write() does, check here: http://java.sun.com/j2se/1.5.0/docs/...intStream.html __________________ "Every gun that is made, every warship launched, every rocket signifies, in the final sense, a theft from those who hunger and are not fed, from those who are cold and are not clothed. The world in arms is not spending money alone. It is spending the sweat of its laborers, the genius of its scientists, the hopes of its children." - Dwight D. Eisenhower

Dec 21st, 2005, 7:22 PM	#4
titaniumdecoy Expert Programmer Join Date: Nov 2005 Posts: 908 Rep Power: 3	Try (Toggle Plain Text) String namestr = new String(name); String namestr = new String(name);

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Dec 21st, 2005, 6:22 PM	#3
theguy0000 Programmer Join Date: Jul 2005 Posts: 73 Rep Power: 4	oh... then how do i convert the byte to a string and put it in a variable?

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Programming Forums > Application Development > Java

I/O question