The following program uses command line arguemnts to creat a Scanner object to r
ID: 3811413 • Letter: T
Question
The following program uses command line arguemnts to creat a Scanner object to read from a file. Fill in the blanks to complete this java class.
public class Demo{
public static void main(String[] args) throws FileNotFoundException{
String filename;
if(args._________>0) { filename = ______;}
else { filename=________________;}
______ FileReader = openFile(filename);
}
public static String promptForFileName() {
System.out.println("Enter the file name: ");
Scanner in = new Scanner(System.in);
return in.next();
}
public static Scanner openFile(__________ filename){
File file = new File(_______);
while (!file.exists()) {
file = new File(_______________);}
return new Scanner(________);
}
}
Explanation / Answer
import java.io.File;
import java.util.Scanner;
public class Demo{
public static void main(String[] args) throws FileNotFoundException{
String filename;
if(args.length>0) { filename =promptForFileName();}
else { filename=promptForFileName();}
Scanner FileReader = openFile(filename);
}
public static String promptForFileName() {
System.out.println("Enter the file name: ");
Scanner in = new Scanner(System.in);
return in.next();
}
public static Scanner openFile(String filename){
File file = new File(filename);
while (!file.exists()) {
file = new File(filename);}
return new Scanner(filename);
}
}
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.