Using BufferedReader to read Text File

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I’m having problems with using the BufferedReader

I want to print the 6 lines of a text file:

public class Reader {

public static void main(String[]args) throws IOException{

    FileReader in = new FileReader("C:/test.txt");
    BufferedReader br = new BufferedReader(in);

    while (br.readLine() != null) {
        System.out.println(br.readLine());
    }
    in.close();

}

Now from what I can gather every time I call the readLine() method it automatically advances to the next line.

So I can’t use the condition br.readLine() != null since it’ll already advance it one line and I get the output:

Line 2
Line 4
Line 6

What Condition do I use to check if there is still a new line in the text field.

Thanks in advance!

Answer

This is the problem:

while (br.readLine() != null) {
    System.out.println(br.readLine());
}

You’ve got two calls to readLine – the first only checks that there’s a line (but reads it and throws it away) and the second reads the next line. You want:

String line;
while ((line = br.readLine()) != null) {
    System.out.println(line);
}

Now we’re only calling readLine() once per loop iteration, and using the line that we’ve read both for the “have we finished?” and “print out the line” parts.



Source: stackoverflow