how to identify the special character in data file in java while reading in java?

Question

how to identify the special character in data file in java while reading in java ?

Example: in below text file at line 5 after test5 having the enter character. ho can we know in java while reading the file.

12,test1,test2,test3,test4
13,test2,test2,test3,test4
14,test3,test2,test3,test4
15,test4,test2,test3,test4
16,test5
,test6,test7,test8
17,test4,test2,test3,test4

Answer 1

You can do this using BufferedReader.read() . It reads the file character by character. So, we can check each character to see whether it is a "carriage return" (13), "new line" (10) etc.

In Windows, line break is normally "carriage return" + "new line".

(The file "data.txt" has the text you have mentioned in the question.)

import java.io.*;

public class ReadCharacters
{
  public static void main(String[] args) throws IOException
  {
    BufferedReader reader = new BufferedReader(new FileReader("data.txt"));
    int i;
    int previousI = -1;
    while ((i = reader.read()) != -1)
    {
      if (i == 13)
      {
        System.out.println("Carriage return (\\r) character");
      }
      else if (i == 10)
      {
        System.out.println("New line (\\n) character");
        if (previousI == 13)
        {
          System.out.println("LINE BREAK (\\r\\n) FOUND!\n");
        }
      }
      else
      {
        System.out.println((char) i);
      }
      previousI = i;
    }
  }
}

Output is:

1
2
,
t
e
s
t
1
,
t
e
s
t
2
,
t
e
s
t
3
,
t
e
s
t
4
Carriage return (\r) character
New line (\n) character
LINE BREAK (\r\n) FOUND!

1
3
,
t
e
s
t
2
...