How To - Read TextFile into Array

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Description:

These are many ways to read a text-file into an array.

myTextFile.txt

2014-12-01 Durban to Cape Town
2014-12-04 Port Elizabeth to Durban
2014-12-05 Durban to Kimberley
2014-12-05 Durban to Potchefstroom
2014-12-07 Potchefstroom to Durban
2014-12-09 Durban to Bloemfontein

Most Common Method: Using Scanner & String[] Arrays

This is the most used method, as it is used to easily split the contents of a Text File line by line into a String Array:

public void readTextFile(String fileName) throws FileNotFoundException {
        String content = "";
        Scanner myTextFile = new Scanner(new FileReader(fileName)).useDelimiter(",\\s*");

        while (myTextFile.hasNext()) {
            // All the contents of the Text File are added to the "content variable
            content = myTextFile.next();
        }
        myTextFile.close();
        // Creating a String Array to store each individual line
        String[] lines = content.split("\n");

        /* The contents of the text file stored in the String variable "contents"
        is being split line by line into the String Array.

        The contents are being split into lines using the String.split(Regex) method, where "Regex" stands for
        any given "regular expression" and "String" is your String variable

        The String.split(Regex) method splits this string around matches of the given regular expression.

        */
    }

Alternate Method: Using Scanner & ArrayLists

Here is the code for this method:

public class ReadTextFile {

    public static void main(String[] args) throws IOException {
    // TODO code application logic here

        // create String variable to store each line
        String line = "";

        // create Scanner
        Scanner myFile = new Scanner(new FileReader("myTextFile.txt")).useDelimiter(",\\s*");

        ArrayList<String> tempArray = new ArrayList<String>(); // Using ArrayList to temporary store values.
        //ArrayLists are better suited than Arrays for this as you don't have to declare memory space for them.

        // while loop
        while (myFile.hasNext()) {
            // find next line
            line = myFile.next();
            tempArray.add(line); // Adding line to ArrayList
        }
        myFile.close();

        //Converting ArrayList to Array using .toArray() Method
        String[] myStringArray = tempArray.toArray(new String[0]);

        for (String outputLine : myStrinArray) {
            System.out.print(outputLine);
        }
    }
}
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