Why am I getting this exception?

Question

i'm running my program, and trying to launch the "help" menu from the program being run from that program (if that makes any sense!). But I'm getting a "NoSuchElement" exception, one that isn't even called in my try {} catch() , in either program! What I'm doing is; Running the program. Typing "create" to launch the commandCreate class. I then type in "help" to launch the help menu. But I get the NoSuchElement exception. If anyone is able to help me with this, my two programs are below. Thank you.

main.java

// main.java
import java.io.*;

public class Main extends API {
      boolean _active = true;
     String _username = System.getProperty("user.name").toLowerCase();
     String _os = System.getProperty("os.name").trim().toLowerCase();

    public Main() {
         try {
            while(_active) {
                BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
                print(_username + "@" + _os + ":~$ ");
                String command = br.readLine();
                    if(command.equalsIgnoreCase("create")) {
                        new commandCreate();
                    /*} else if(command.equals("compile")) {
                        new commandCompile();*/
                    } else if(command.equalsIgnoreCase("help")) {
                        println("Commands");
                        println(" create              - Creates .java files, does not compile.");
                        //println(" compile             - Creates .java files, compiles on creation.");
                        println(" exit                - Exits program");
                        println(" help                - Shows help documentation.");
                    } else if(command.equalsIgnoreCase("exit")) {
                        print("Are you sure you want to exit? (Y/N) ");
                        String exit = br.readLine();
                        if(exit.equalsIgnoreCase("y")) {
                        exit();
                        } else {
                        println("Cancelled!");
                        }
                    } else if(command.isEmpty()) {

                    } else {
                        println("\"" + command + "\" does not exist. Please review the \"help\" menu");
                    }
            }
        } catch(Exception ex) {
            println("There was a problem: " + ex);
            }
   }

    public static void main(String[] args) {
     new Main();
    }
}

commandCreate.java

// commandCreate.java
import java.util.*;
import java.io.*;

public class commandCreate {
    boolean _active = true;
   String _username = System.getProperty("user.name").toLowerCase();
   String _os = System.getProperty("os.name").trim().toLowerCase();
   String fileName, create, option;

    public commandCreate() {
        try {
            System.out.print(_username + "@" + _os + ":~/create$ ");
            Scanner kbd = new Scanner(System.in);
                String userLine = kbd.nextLine();

            Scanner read = new Scanner(userLine);
                option = read.next();
                fileName = read.next();

            FileWriter create = new FileWriter(new File("Created Files/" + fileName + ".java"));

            if(userLine.equals(option + " " + fileName)) {
                if(option.equals("-a")) {
                    // Option = -a, creates standard file with main class.
                    create.write("public class " + fileName + " {\n");
                    create.write("  public static void main(String[] args) {\n");
                    create.write("      System.out.println(\"Welcome to your new program!\");\n");
                    create.write("  }\n");
                    create.write("}");
                } else if(option.equals("-c")) {
                    // Option = -c , creates standard file with overloaded constructor & main class.
                    create.write("public class " + fileName + " {\n");
                    create.write("  public " + fileName + "() {\n");
                    create.write("      System.out.println(\"Welcome to your new program!\");\n");
                    create.write("  }\n");
                    create.write("\n");
                    create.write("  public static void main(String[] args) {\n");
                    create.write("      new " + fileName + "();\n");
                    create.write("  }\n");
                    create.write("}");
                } else if(option.equals("-j")) {
                    // Option = -j, creates GUI within constructor w/ single JLabel.
                    create.write("import javax.swing.*;\n");
                    create.write("import java.awt.*;\n");
                    create.write("import java.awt.event.*;\n");
                    create.write("\n");
                    create.write("public class " + fileName + " extends JFrame {\n");
                    create.write("  private static final int HEIGHT = 50;\n");
                    create.write("  private static final int WIDTH = 400;\n");
                    create.write("\n");
                    create.write("  private JLabel welcomeJ;\n");
                    create.write("\n");
                    create.write("  public " + fileName + "() {\n");
                    create.write("    super(\"Welcome to your program - " + fileName + "\");\n");
                    create.write("      Container pane = getContentPane();\n");
                    create.write("    setLayout(new FlowLayout());\n");
                    create.write("\n");
                    create.write("      welcomeJ = new JLabel(\"Welcome To Your Program!\", SwingConstants.CENTER);\n");
                    create.write("\n");
                    create.write("      pane.add(welcomeJ);\n");
                    create.write("\n");
                    create.write("     setSize(WIDTH, HEIGHT);\n");
                    create.write("     setVisible(true);\n");
                    create.write("     setResizable(false);\n");
                    create.write("     setDefaultCloseOperation(EXIT_ON_CLOSE);\n");
                    create.write("  }\n");
                    create.write("\n");
                    create.write("  public static void main(String[] args) {\n");
                    create.write("      new " + fileName + "();\n");
                    create.write("  }\n");
                    create.write("}");
                }
            } else if(userLine.equalsIgnoreCase("help")) {
                System.out.println("Commands");
                System.out.println("  Syntax: [-option] [filename]");
                System.out.println("      -a [filename]      [Program: main class]");
                System.out.println("      -c [filename]      [Program: overloaded constructor, main class]");
                System.out.println("      -j [filename]      [Program: GUI: overloaded constructor, main class]");
            } else {
                System.out.println("Error in syntax. Please review the \"help\" menu");
            }
            create.close();
        } catch(IOException e) {
            System.out.println("There was an error: " + e);
        } catch(InputMismatchException ex) {
            System.out.println("There was an error: " + ex);
        }
    }

    public static void main(String[] args) {
        new commandCreate();
    }
}

Answer 1

According to your stack-trace, the problem is here:

            Scanner kbd = new Scanner(System.in);
                String userLine = kbd.nextLine();

            Scanner read = new Scanner(userLine);
                option = read.next();
                fileName = read.next();             // <--- exception here

What this bit of code does is this:

• it reads a line from standard-input, and saves it in userLine .
• it reads two whitespace-delimited tokens from userLine , and saves them as option and filename .

So the problem is that the line from standard-input doesn't actually have two whitespace-delimited tokens. It needs to look something like -j file.txt , but instead maybe it just looks like -j , or like file.txt .

Answer 2

You could have a problem in the superclass named API. Look there.