Thread: Java .split not working?

First of all, hello! I am new here, and I come with a very newbish question. For some reason, this decided not to work, and I spent a couple of hours trying to realize why, and I just can't manage to.
Here is the code:

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
 
public class Learn {
 
	public static void readFile(String file) {
		String[] arr;
		BufferedReader br = null;
		ArrayList<String> str = new ArrayList<String>();
		try {
			String currentLine;
			br = new BufferedReader (new FileReader(file));
			while((currentLine = br.readLine()) != null) {
				if(currentLine.contains(".")) {
					arr = currentLine.split(".");
					System.out.println(arr.length);
					for(int i = 0; i < arr.length; i++) {
						System.out.println(arr[i]);
						if(!(arr[i].equals("")))
							str.add(arr[i]);
					}
				}
				for(String st : str) {
					System.out.println(st);
				}
			}
		}
		catch(IOException e) {
			e.printStackTrace();
		}
		finally {
			try {
				if( br != null )
					br.close();
			}
			catch(IOException e) {
				e.printStackTrace();
			}
		}
	}
}

and the file it is reading is

This is a test for sentences. This sentence is one.
This is another

The curentLine.contains(".") expression evaluates to true, but the code stops there (I mean, just skips the rest). I added that println there, and the output is 0; so basically, something goes wrong in the split().
Any help is greatly appreciated!
Thank you for your time!
Best regards,
BrreaKer

The . is a regex special character. Add the escape character: \ to use it as a character. There will need to be two \\s because \ is also a compiler special character.