import java.io.*;
import java.util.*;

public class ThrowException {
  
  public static double addFileContents(String path) throws NegativeValueException {
    
    Scanner sc=null;

    try {
      File file = new File (path);
      sc = new Scanner(file);
      double sum = 0.0;
      while(sc.hasNextDouble()) {
        double value = sc.nextDouble();
        if(value<0)
          throw new NegativeValueException();
        sum += sc.nextDouble();
      }
    }
    catch(FileNotFoundException ex) {
      System.out.println("The specified file was not found at "+ path);
    }
    catch(NoSuchElementException ex) {
      System.out.println("The specified type of element was not found!");
    }
    finally {
      System.out.println("Closing File!");
      sc.close();
    }
    return 0.0;
  }
  
  public static void main(String args[]) {
    try {
      double result = addFileContents(args[0]);
      System.out.println("Result is: "+result);
    }
    catch(IndexOutOfBoundsException ex) {
      System.out.println("No file has been specified from command line!\n");
    }
    catch(NegativeValueException ex) {
      System.out.println("The file contains negative value");
    }
  }

}