Read the content of a text file then convert it its decimal equivalent

Good morning,
I am very new to java, I am trying to read a binary value from a text file to assign it to a variable in java, to then convert it to its decimal number equivalent.

With the code down below I can do this up to having thirty-one "1" and "0" in my text file:

import java.io.*;
public class ReadBin
{  
    public static void main(String[] args)
  {
    try
    {
      BufferedReader input = new BufferedReader(new FileReader("test.txt"));
      String line = input.readLine();  
      while (line != null)
      {
        //String line contains a number in binary format, now convert it  
        int value = Integer.parseInt(line, 2);

        System.out.println("Read value: " + value);
        // Read next line  
        line = input.readLine();
      }  
      input.close();  
    }
    catch (Exception e)
    {
      System.out.println(e.getMessage());  
    }  
    }
  }

I need the ability to convert up to one thousand binary bits not thirty one. with the code down below I can achieve that:
public class test2
{
public static void main(String args[])
{
String bin = "1111111111111111111111111";
double ctr=1, decimal=0;

for (double i = bin.length()-1; i>=0; i--)
{
if(bin.charAt((int) i)=='1')
decimal+=ctr;
ctr*=2;
}
System.out.println ("Decimal: "+decimal);
}
}


In the String bin = "1111111111111111111111111"; location I can put one thousand "1" and "0" and it gives me the right answer.

Could some help me put these together so I can read and convert to decimal a binary number of a length up to one thousand "1" and "0" from the text file.

Thank you for your help,

John
lebouffonvertAsked:
Who is Participating?
 
objectsConnect With a Mentor Commented:
use a BigInteger then

BigInteger bi = new BigInteger(line, 2);

0
 
MicheleMarconCommented:

String s="";
    try {
      is = new DataInputStream(new FileInputStream("1000bytes.txt"));
      while (true) { // exception deals catches EOF
        ch = is.readByte();
        s+=((char) ch);
      }
    } catch (EOFException eof) {
      System.out.println(" Finished!");
    }

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0
 
objectsCommented:
       long value = Long.parseLong(line, 2);

0
 
lebouffonvertAuthor Commented:
Thank you for such a quick reply to both of you.

Michele Marcon,  if I may ask the example you gave me is for reading the file correct? because I can't see where it is manipulating the binary number to convert it to its decimal equivalent.

objects:
long value = Long.parseLong(line, 2);
I tried it and it works well up to 63 bytes but then it stop converting and gives me a read out of all binary numbers
0
 
lebouffonvertAuthor Commented:
Thank you so much for your help.
It was really helpfull
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