The java.util.Scanner class (added in Java 5) allows simple console and file input. Of course, your program should eventually have a GUI user interface, but Scanner is very useful for reading data files.
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// File : introductory/IntroScanner.java // Purpose: Write to and read from the console. // Author : Michael Maus // Date : 2006-01-20 import java.util.*; //Note 1 public class IntroScanner { public static void main(String[] args) { //... Initialization String name; // Declare a variable to hold the name. Scanner in = new Scanner(System.in); //... Prompt and read input. System.out.println("What's your name, Earthling?"); name = in.nextLine(); // Read one line from the console. in.close(); //Note 2 //... Display output System.out.println("Take me to your leader, " + name); } } |
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// File : introductory/ScannerLoop.java // Purpose: Read from the console in a loop using Scanner. // Author : Michael Maus // Date : 2006-01-20 import java.util.*; public class ScannerLoop { public static void main(String[] args) { //... Initialization double n; // Holds the next input number. double sum = 0; // Sum of all input numbers. Scanner in = new Scanner(System.in); //... Prompt and read input in a loop. System.out.println("Will add numbers. Non-number stops input."); while (in.hasNextDouble()) { n = in.nextDouble(); sum = sum + n; } in.close(); //... Display output System.out.println("The total is " + sum); } } |