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Java

Posted by Matthew McGeehan
Matthew McGeehan
995 Points

Using an outside IDE in Java???

Hello All,

I tried running the following code in Dr. Java:

import java.io.Console;

public class TreeStory {

    public static void main(String[] args) {
        Console console = System.console();
        /*  Some terms:
            noun - Person, place or thing
            verb - An action
            adjective - A description used to modify or describe a noun
            Enter your amazing code here!
        */
     // __Name__ is a __adjective__ __noun__. They are always __adverb__ __verb__
      String name = console.readLine("Enter a name:  ");
      String adjective = console.readLine("Enter an adjective:  ");
      String noun = console.readLine("Enter a noun:  ");
      String adverb = console.readLine("Enter an adverb:  ");
      String verb = console.readLine("Enter a verb ending with -ing:  ");

      console.printf("Your TreeStory:\n-----\n");
      console.printf("%s is a %s %s.  ", name, adjective, noun);
      console.printf("They are always %s %s. \n", adverb, verb);
    }
}

In Dr. Java, I am unable to type in the console, but I am able to type in the "interactions" at the bottom of the Dr. Java IDE. Is this where I should be running:

clear && javac TreeStory.java && java TreeStory

I tried that but just received errors. Do I need to point to a directory perhaps?

Sorry for my newb questions.

2 Answers

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi,

I just downloaded Dr Java to see the solution for this.

Have you tried clicking the compile button at the top (that does the javac bit) then the Run button?

I get an error but that's how the Dr Java thing is supposed to work, I think.

Steve.

Matthew McGeehan
Matthew McGeehan
995 Points
Matthew McGeehan
Matthew McGeehan
995 Points

Thank for the reply Steve,

I clicked the compile button, Compilation completed, then I clicked the run button and received this in my "interactions":

Welcome to DrJava. Working directory is /Users/"myname"/Desktop

run TreeStory java.lang.NullPointerException at TreeStory.main(TreeStory.java:15) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)

When I run the TreeStory.java in Terminal, the program works perfectly, but I was hoping to make it work in Dr. Java as well. Perhaps, there is a different syntax I should be using somewhere along the way. I'll do some googling and report back if I find an answer,

Thanks again Steve.