Read a File

Write a program that reads and properly parses a file called "people.txt" which contains the name of the person followed by his age and then his height in feet. A sample file looks like:

Mario 34 4.5
Donkey Kong 15 5.7
Luigi 38 5.8
Princess Peach Toadstoll 25 5.2

A very easy question. You need to remember how to loop to read a file and, more importantly, that this data should go into a record or class. Since each row represents a person, a good programmer should initially default to thinking about each row as an object with various attributes.

The only tricky part in this example is the fact that a person's name could be any number of words. Thus, we have to look for the first integer before we can declare that the complete name has been found.

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

public class Person {
  private String name;
  private int age;
  private double height;

  public Person (Scanner in){
    name = "";
    while (!in.hasNextInt()){
      name += in.next() + " ";
    }
    age = in.nextInt();
    height = in.nextDouble();
    in.nextLine();
  }

  public String toString(){
    return name + " " + age + " " + height;
  }

  public static void main (String[] args){
    String filename = "people.txt";
    try {
      Scanner in = new Scanner(new File(filename));
      while (in.hasNextLine()){
        Person p = new Person(in);
        System.out.println(p);
      }
    } catch (FileNotFoundException e){
      System.out.println("Sorry, could not find file " + e);
    }
  }
}