How to read N amount of lines from a file?
arraylist, bufferedreader, fileinputstream, for-loop, java
Solution
You could try using a Scanner and a counter:
ArrayList<Double> array = new ArrayList<Double>();
Scanner input = new Scanner(new File("numbers.txt"));
int counter = 0;
while(input.hasNextLine() && counter < 10)
{
array.add(Double.parseDouble(input.nextLine()));
counter++;
}
This should loop through 10 lines adding each to the arraylist as long as there is more inputs in the file.
Problem
I am trying to practice reading text from a file in java. I am little stuck on how I can read N amount of lines, say the first 10 lines in a file and then add the lines in an `ArrayList`. Say for example, the file contains 1-100 numbers, like so; ``` - 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - .... ``` I want to read the first 5 numbers, so 1,2,3,4,5 and add it to an array list. So far, this is what I have managed to do but I am stuck and have no clue what to do now. ``` ArrayList<Double> array = new ArrayList<Double>(); InputStream list = new BufferedInputStream(new FileInputStream("numbers.txt")); for (double i = 0; i <= 5; ++i) { // I know I need to add something here so the for loop read through // the file but I have no idea how I can do this array.add(i); // This is saying read 1 line and add it to arraylist, // then read read second and so on } ```