Java

public class TextFileReader {
	public interface ScannerOperation {
		void handleNext(Scanner sc);
	}
	
	/**
	 * @param path The path of the file as a string.
	 * @param f Lambda function to apply. Should advance to the next token in
	 *  some way.
	 * @throws IOException
	 */
	public static void readTextFile(String path, ScannerOperation f) throws IOException {
		File inputFile = new File(path);
		try (Scanner sc = new Scanner(inputFile)) {
			while (sc.hasNext()) {
				f.handleNext(sc);
			}
		}
	}
}

public class ExampleImplementation {
	public static void main(String[] args) {
		try {
			TextFileReader.readTextFile("file.txt", (sc) -> {
				System.out.println(sc.next());
			});
		} catch (IOException e) {
			System.err.println(e.toString());
			return;
		}
	}
}