The function keep looping

[stegano]

Hello.im having problem with my program.this program actually to con vert to different texts into binary.the problem is,it keep looping even after the second text was converted.anyone,plz help me.

import java.util.*;
import java.io.*;
public class textconversion{
public static void main(String[] args) {

do{
	Scanner input = new Scanner(System.in);
	System.out.println ("Enter Text to Convert: ");
	String msg = input.nextLine();
	
  
  byte[] bytes = msg.getBytes();
  StringBuilder binary = new StringBuilder();
  for (byte b : bytes)
  {
     int val = b;
     for (int i = 0; i < 8; i++)
     {
        binary.append((val & 128) == 0 ? 0 : 1);
        val <<= 1;
     }
     binary.append(' ');
  }
	System.out.println();
	System.out.println();
  	System.out.println("Your Text"+" <" + msg + "> Successfully Converted Into Binary: "+binary);
	System.out.println();
	
	

}
 	 while (true);
	
	
}

}

[KevinWorkman]

I'm not sure what your question is. This seems to do what you would expect. You have a while(true) there, so it's going to loop forever.

What did you expect to see instead?

[stegano]

actually,i want to stop this loop after the second loops.tq

[JosAH]

actually,i want to stop this loop after the second loops.tq

Then don't use a do { ... } while (true); loop. It loops forever. I'm sure you can create a loop that only loops twice. <--- hint: a for-loop can do it.

kind regards,

Jos

[stegano]

my mistakes..thanks

[eXistenZ]

OK. What is the consensus from the more experienced on this:

while (true) {

get input from user;

if (some signal)
 break;

}

continue processing

Acceptable? What's the policy on "breaks" in loops?

[sunde887]

Im not sure what exactly the policy is, I have no problem using breaks where necessary. In a while(true) loop there is no other way(that I know of) to get out of it.

[Junky]

Im not sure what exactly the policy is, I have no problem using breaks where necessary. In a while(true) loop there is no other way(that I know of) to get out of it.

If it is in a method you can use the return statement.

public void doStuff(int number) {
    while(true) {
        System.out.println(number);
        if(number % 5 ==0) {
            return;
        } else {
            number += 3;
        }
    }
}

Personally I dislike while(true) loops. I prefer to use a boolean.

boolean flag = true;
while(flag) {
    // do stuff
    if(condition) {
        flag = false;
    }
 }

[sunde887]

I'm wondering as well if people can explain what the general consensus on the use of breaks is, and why they are frowned upon if they are?

And good idea on the use of return instead in methods.

[gcalvin]

I don't think they're frowned upon, but if you take a step back, your code should be expressive of what you're trying to do, and not merely be the mechanism for getting a certain result. In other words, a while (true) loop with a break is perfectly fine if the idea is that the loop will continue to execute during normal operation, and break at some exceptional condition (or perhaps one of several exceptional conditions). But if, as in this case, the loop is meant to execute exactly two times, a while (true) with a break seems an odd choice. It doesn't communicate intent well, it's confusing to anyone reading your code, and it will be confusing to you when you look at it again after a few months.

-Gary-

[KevinWorkman]

Like many things in programming, there is no "consensus" on this. Does it get the job done and fit inside your head? Then use it.

The reason there is no consensus is that it depends entirely on the context of the program, including who the programmer is. You can't really ask "what is the consensus on this general concept?" because it really depends on the specifics.

[stegano]

does anyone here know what i need to add in order to do encryption in the code above?

[JosAH]

does anyone here know what i need to add in order to do encryption in the code above?

Yep, write a separate encrypt( ... ) method. We don't know what you want to encrypt and we don't know what that method is supposed to return so you have to decide. But whatever you decide, don't decide to cram that code in the same method as the code above.

kind regards,

Jos