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add example for terminal
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lines changed

8 files changed

+249
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‎.DS_Store

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‎HelloWorldTerminal.zip

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‎HelloWorldTerminal/ConsoleProgram.class

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‎HelloWorldTerminal/ConsoleProgram.java

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import java.util.Scanner;
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public class ConsoleProgram{
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private Scanner scanner;
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public static void main(String[] args){
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// Assume the class name is passed in as the first argument.
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if(args.length == 0){
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System.out.println("Please provide the name of the main class as an argument.");
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return;
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}
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String mainClassName = args[0];
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try{
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Class mainClass = Class.forName(mainClassName);
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Object obj = mainClass.newInstance();
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ConsoleProgram program = (ConsoleProgram)obj;
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program.run();
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} catch (IllegalAccessException ex) {
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System.out.println("Error in program. Make sure you extend ConsoleProgram");
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} catch (InstantiationException ex) {
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System.out.println("Error in program. Make sure you extend ConsoleProgram");
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} catch (ClassNotFoundException ex) {
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System.out.println("Error in program. Make sure you extend ConsoleProgram");
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}
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}
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/**
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* The run method is overwritten by the subclass. This is the main entry point for
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* ConsolePrograms. There is no main method in student programs that extend ConsoleProgram,
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* instead they write their application starting like this:
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*
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* public void run()
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* {
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* // student code here
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* }
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*
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* The main method of ConsoleProgram calls this run method when it begins.
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*/
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public void run(){
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/* Overridden by subclass */
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}
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/**
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* Constructor for Console program. Create a scanner instance to be used for user input.
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*/
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public ConsoleProgram(){
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scanner = new Scanner(System.in);
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}
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/**
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* This method reads a line of input from the user, given a prompt.
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*
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* @param prompt A prompt to the user to get input
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* @return A String of the user input.
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*/
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public String readLine(String prompt){
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System.out.print(prompt);
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return scanner.nextLine();
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}
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/**
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* This method reads a boolean value from the user, asking them for either
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* a true or false value. This makes use of the readLine method.
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*
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* @param prompt A prompt to the user to read a boolean value
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* @return A boolean value read from the user.
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*/
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public boolean readBoolean(String prompt){
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while(true){
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String input = readLine(prompt);
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if(input.equalsIgnoreCase("true")){
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return true;
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}
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if(input.equalsIgnoreCase("false")){
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return false;
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}
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}
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}
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/**
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* This method reads a double value from the user, given a prompt.
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*
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* @param prompt A prompt to the user to ask for a a double.
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* @return A double value read from the user.
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*/
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public double readDouble(String prompt){
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while(true){
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String input = readLine(prompt);
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try {
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double n = Double.valueOf(input).doubleValue();
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return n;
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} catch (NumberFormatException e){
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}
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}
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}
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/**
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* This method reads a int value from the user, given a prompt.
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*
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* @param prompt A prompt to the user to ask for an int
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* @return The int value read from the user.
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*/
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public int readInt(String prompt){
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while(true){
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String input = readLine(prompt);
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try {
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int n = Integer.parseInt(input);
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return n;
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} catch (NumberFormatException e){
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}
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}
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}
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}

‎HelloWorldTerminal/Hello.class

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‎HelloWorldTerminal/Hello.java

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public class Hello extends ConsoleProgram
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{
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public void run()
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{
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System.out.println("Hello World!");
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}
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}

‎HelloWorldTerminal/Randomizer.java

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import java.util.Random;
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public class Randomizer{
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public static Random theInstance = null;
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public Randomizer(){
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}
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public static Random getInstance(){
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if(theInstance == null){
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theInstance = new Random();
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}
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return theInstance;
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}
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/**
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* Return a random boolean value.
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* @return True or false value simulating a coin flip.
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*/
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public static boolean nextBoolean(){
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return Randomizer.getInstance().nextBoolean();
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}
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/**
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* This method simulates a weighted coin flip which will return
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* true with the probability passed as a parameter.
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*
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* @param probability The probability that the method returns true, a value between 0 to 1 inclusive.
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* @return True or false value simulating a weighted coin flip.
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*/
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public static boolean nextBoolean(double probability){
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return Randomizer.nextDouble() < probability;
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}
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/**
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* This method returns a random integer.
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* @return A random integer.
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*/
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public static int nextInt(){
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return Randomizer.getInstance().nextInt();
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}
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/**
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* This method returns a random integer between 0 and n, exclusive.
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* @param n The maximum value for the range.
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* @return A random integer between 0 and n, exclusive.
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*/
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public static int nextInt(int n){
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return Randomizer.getInstance().nextInt(n);
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}
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/**
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* Return a number between min and max, inclusive.
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* @param min The minimum integer value of the range, inclusive.
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* @param max The maximum integer value in the range, inclusive.
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* @return A random integer between min and max.
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*/
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public static int nextInt(int min, int max){
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return min + Randomizer.nextInt(max - min + 1);
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}
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/**
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* Return a random double between 0 and 1.
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* @return A random double between 0 and 1.
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*/
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public static double nextDouble(){
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return Randomizer.getInstance().nextDouble();
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}
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/**
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* Return a random double between min and max.
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* @param min The minimum double value in the range.
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* @param max The maximum double value in the rang.
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* @return A random double between min and max.
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*/
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public static double nextDouble(double min, double max){
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return min + (max - min) * Randomizer.nextDouble();
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}
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}

‎index.html

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@@ -51,6 +51,7 @@ <h1 class="logo pull-left">
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<li class="nav-item"><a class="scrollto" href="#docs">Quick Start</a></li>
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<li class="nav-item"><a class="scrollto" href="#eclipse">Eclipse</a></li>
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<li class="nav-item"><a class="scrollto" href="#bluej">BlueJ</a></li>
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<li class="nav-item"><a class="scrollto" href="#terminal">Terminal</a></li>
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</ul><!--//nav-->
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</div><!--//navabr-collapse-->
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</nav><!--//main-nav-->
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<ol>
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<li>Download the zip of the <a href="HelloWorldBluejay.zip">Hello project.</a> and unzip it.</li>
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<li>Double click the package.bluej file to open the BlueJ project</li>
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<li>Right click on ConsoleProgram and select "void main(String[] args)"</li>
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<li>Right click on Hello and select "void main(String[] args)"</li>
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<li>Then as the arguments type {"Hello"}</li>
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<img src="https://www.evernote.com/l/AATC9IIdGwlFGp9SPTu797Eq573OIoLWZHYB/image.png" width="600">
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<img src="https://www.evernote.com/l/AATTD_1yydpGp5BOJNJdhgFUocru7GBhYkYB/image.png" width="600">
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</ol>
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</div><!--//block-->
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</section><!--//features-->
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<section id="terminal" class="docs section">
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<div class="container">
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<div class="docs-inner">
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<h2 class="title text-center">Running in the Terminal</h2>
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<div class="block">
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<h3 class="sub-title text-center">Java HelloWorld in the Terminal</h3>
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<ol>
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<li>Download the zip of the <a href="HelloWorldTerminal.zip">Hello project</a> and unzip it.</li>
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<li>Save it to the Downloads folder. If you save it somewhere else then you will need to navigate
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there in the terminal using <code>ls</code> and <code>cd</code>.</li>
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<li>Open your terminal (on Macs the Terminal app)</li>
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<li>Change to the right directory. If you put it in Downloads it will be:
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<pre>cd Downloads/HelloWorldTerminal</pre>
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otherwise it will be in a different folder.
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<li>Compile the code with <pre>javac Hello.java</pre></li>
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<li>Run the code with <pre>java Hello Hello</pre> What's happening here is we are running the program
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called Hello and passing it as an argument the String "Hello" so that it knows which file to run.</li>
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<img src="https://www.evernote.com/l/AATjorYeCmhDRrA79d3IhjMAxgn2Co-jUjYB/image.png" width="600">
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</ol>
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</div><!--//block-->
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</div><!--//docs-inner-->
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</div><!--//container-->
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</section><!--//features-->
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<!-- ******FOOTER****** -->
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<footer class="footer">
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<div class="container text-center">

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