Write a program that outputs the number of characters, words, and lines in the files that are supplied as command-line arguments.

Public class Exercise_13 {

public static void main(String[] args) {

if (args.length != 1) {
System.out.println("Invalid arguments.");
System.out.println("Usage: java Chapter_12.Exercise_13 filename");
System.exit(1);
}
File filename = new File(args[0]);
if (!filename.exists()) {
System.out.println(filename + " does not exist.");
System.exit(2);
}

int characters = 0;
int words = 0;
int lines = 0;

try {
Scanner input = new Scanner(filename);
while (input.hasNext()) {
String s = input.nextLine();
lines++;
characters += s.length();
String[] split = s.split(" ");
for (String word : split) {
words++;
}
}

} catch (FileNotFoundException ex) {
ex.printStackTrace();
}

System.out.println("Characters: " + characters);
System.out.println("Words: " + words);
System.out.println("Lines: " + lines);

}
}