Solved

Getting bytes from the bytes array

Posted on 2006-10-21
5
205 Views
Last Modified: 2010-03-31
Hi Friends,
I receive data from the server and I store it in a bytes array.Now I need to retrieve bytes from the array,like first byte says code[1 byte],second says lastname[4 bytes],third says fname[30 bytes],last byte says if there is one more entry,and the same syntax needs to be followed again....I tried this but its not working...any help would be appreciated.


import java.io.*;
import java.nio.*;
 
public class btest{
public static void main(String[] ar){
 try{
 
                String data1 ="1232 3 3 444 222 111 444 555555 2222222 1111111 3333 dssssddd";
                byte[] data = data1.getBytes("ASCII");
            int length = data.length;
            System.out.println("length is:"+length);
            ByteBuffer buff = ByteBuffer.wrap(data);
 
            byte[] fbyte = new byte[1];
            byte[] lname = new byte[4];
            byte[] fname = new byte[30];
            byte[] lbyte = new byte[1];
            
            buff.get(fbyte, 0,1);
            String received0 = new String(fbyte,"ASCII");
                System.out.println("Data Recd: " + received0);
            buff.position(1);
            
            buff.get(ref_no, 1,4);            
            String received1 = new String(lname,"ASCII");
            buff.position(4);
 
            buff.get(uname, 4,34);
              String received2 = new String(fname,"ASCII");
                System.out.println("Data Recd: " + received2);
            buff.position(34);
 
            buff.get(lbyte, 34,35);
            String received3 = new String(lbyte,"ASCII");
                System.out.println("Data Recd: " + received3);
 
}catch(Exception e){e.printStackTrace();}
 
}
}

0
Comment
Question by:harmeek_80
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
5 Comments
 
LVL 86

Expert Comment

by:CEHJ
ID: 17782874
You don't need to move anything or calculation positions - the BB will do that for you

buff.get(fbyte);
String received0 = new String(fbyte,"ASCII");
System.out.println("Data Recd: " + received0);

buff.get(ref_no);


etc.
0
 
LVL 92

Expert Comment

by:objects
ID: 17782939
>           buff.get(ref_no, 1,4);          

your problem is that those values refer to where in ref_no to place the bytes :)

What you want can also easily be done without even needing to create a ByteBuffer, and use Syste.arraycopy to copy the bytes directly from the byte array
0
 
LVL 86

Assisted Solution

by:CEHJ
CEHJ earned 50 total points
ID: 17782950
It's actually easier to do it with a BB - it's been designed especially for this sort of thing
0
 
LVL 92

Accepted Solution

by:
objects earned 100 total points
ID: 17782969
you also need to remove those calls to position (they are relative gets) and do it in a loop
there are a variety of other minor prob also with the code
try something like:

boolean done = false;
while (!done) {
          buff.get(fbyte);
          String received0 = new String(fbyte,"ASCII");
          System.out.println("Data Recd: " + received0);
         
          buff.get(fname);
          String received1 = new String(fname,"ASCII");
          System.out.println("Data Recd: " + recieved1);
 
          buff.get(lname);
          String received2 = new String(lname,"ASCII");
          System.out.println("Data Recd: " + recieved2);

          buff.get(lbyte);
          String received3 = new String(lbyte,"ASCII");
          System.out.println("Data Recd: " + received3);
          done = !recieved3.equals(MORE_DATA);
}
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 17784478
Not sure how that answer added anything to the one i'd already given, although it did repeat it
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In this post we will learn how to connect and configure Android Device (Smartphone etc.) with Android Studio. After that we will run a simple Hello World Program.
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
Viewers learn how to read error messages and identify possible mistakes that could cause hours of frustration. Coding is as much about debugging your code as it is about writing it. Define Error Message: Line Numbers: Type of Error: Break Down…
Viewers will learn how to properly install Eclipse with the necessary JDK, and will take a look at an introductory Java program. Download Eclipse installation zip file: Extract files from zip file: Download and install JDK 8: Open Eclipse and …

740 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question