Installing JavaScript

• Windows
• Mac
• Linux

Windows Instructions:

This document describes the basic steps for installing Rhino for JavaScript on a Windows machine for use with TextPad.

• Download and install Textpad

• Get Rhino from the Rhino download site. Or download the key file you need, rhino.jar, directly from our course web site. Save it in a directory that is somewhat permanent, such as C:\rhino . To configure TextPad for color syntax highlighting:
  1. Download javascript.syn to the Samples subfolder of your TextPad installation (on my Windows XP computer it was "C:\Program Files\TextPad 5\Samples" and on my 64-bit machine it was "C:\Program Files (x86)\TextPad 5\Samples." Note: On my Windows Vista machine, the folder was set to "read only", so I saved the file to the desktop, dragged it to the correct folder, and told the computer that it was okay to apply administrator privileges.

  2. In TextPad, select Configure, New Document Class with the following settings:

     Document class name: JavaScript
     Class members:       *.js
     

     When it prompts for syntax file name, select javascript.syn and click on "Enable syntax highlighting".

  3. Test it by typing in some JavaScript code like the following:

     function foo() {
         print("Hello, world!");
     }
     foo();   // call the function
     

     Save it to test.js. When you go to save, be careful to have "Save as Type" set to "All files". TextPad has a habit of saving to Text files in which case it would save it as test.js.txt. When you save it, you should see colors appear for the keywords.

  Below are three optional configurations that you might want to do:
  • Go to Configure, Preferences, File Name Filters and create a new filter with these settings:

    Description: JavaScript files
    Wildcards:   *.js
    

    You can then click on the "Move up" button several times to move it to the top so that TextPad will default to the sml file type. Be sure to click on Apply and OK.

  • Go to Configure, Preferences, Associated Files. In the "New Extension" text field, type .js and in the Description text field, type something like "JavaScript files". Then click on Add, Apply, OK. Once you've done this, you can double-click on your .js files and they'll open in TextPad.

  • By default we get tabs every 8 spaces. This is not the best choice for JavaScript. Tabs every 4 spaces works out well. So go to Configure, Preferences, open the "+" tab for Document Classes and open the "+" tab for SML. Then select Tabulation. I recommend setting both "default tab spacing" and "indent size" to 4 and selecting "Convert new tabs to spaces." It's safest to have spaces in your file rather than tabs. Otherwise you'll find that it looks different when you're not in TextPad. For example, you might go to the trouble to have excellent indentation that looks horrible to the graders because they aren't using TextPad.

  This final step is the most tricky but also probably the most useful. You can define a tool that will allow you to run a file in Rhino. Here are the basic steps to follow:
  1. Go to Configure, Preferences, Tools and select Add and then select Program.

  2. The program you want it to run is called java.exe and you'll find it in the directory c:\Program Files\Java\jdk_VERSIONNUMBER\bin (it was c:\Program Files (x86)\Java\jdk_VERSIONNUMBER\bin on my 64-bit machine). Navigate to the file, select it, and then click on Apply.

  3. Expand the Tools menu (you'll probably see a "+" that you need to click on). Under that, select the java command you just created. You need to change a few settings. Change the "Parameters" from $File to -jar "PATH_TO_RHINO.JAR" $File (no quotes). Uncheck the box for "Capture output". Check the box for "Save all documents first". Leave everything else alone. Click on Apply and OK.

     

     • NOTE: If you are writing a program that doesn't produce console output, such as a file that just defines a bunch of functions and types (which is true of some of our homework), then running Rhino in the above way won't be useful, because the program actually produces no output. In ML, the interpreter would handle this by loading all of our functions and then putting you at the interpreter REPL prompt to try out your functions. Rhino does not; it loads all of your functions and then exits the interpreter.

       So you may instead want to set your "Parameters" to just "-jar PATH_TO_RHINO.JAR" , and then make sure the "Initial Folder" is set to $FileDir . Then when you run Rhino you will get an empty interpreter, where you can type:

       load("YOUR_FILE_NAME.js");
       

  4. (optional) Set up a separate tool for the Rhino debugger. Again click Configure, Preferences, Tools and select Add and then select Program.

     The program you want it to run is called javaw.exe (note the W) and you'll find it in the directory c:\Program Files\Java\jdk_VERSIONNUMBER\bin (it was c:\Program Files (x86)\Java\jdk_VERSIONNUMBER\bin on my 64-bit machine). Navigate to the file, select it, and then click on Apply.

     Expand the Tools menu (you'll probably see a "+" that you need to click on). Under that, select the javaw command you just created. You need to change a few settings. Change the "Parameters" from $File to -classpath "PATH_TO_RHINO.jar" org.mozilla.javascript.tools.debugger.Main $File (no quotes). Uncheck the box for "Capture output". Check the box for "Save all documents first". Leave everything else alone. Click on Apply and OK.

  You should now find a selection under the Tools/External Tools menu called java. You may want to rename it to something like "Run in Rhino". (Ditto for the debugger one; maybe rename it to "Debug in Rhino".) Try selecting it. It should launch the interpreter, load your file, and leave you at a prompt to interact with the interpreter.

  Mac Instructions:

  On Mac, just save rhino.jar to a known directory on your machine. To run the interpreter, open a Terminal and type:

  java -jar PATH_TO_RHINO\rhino.jar
  

  or, to run a .js file as a program, type:

  java -jar PATH_TO_RHINO\rhino.jar filename
  

  I don't use a Mac and don't know Mac text editors, so I don't have any detailed instructions for setting them up. If you find a way to integrate Rhino/JavaScript with your editor, feel free to post about this on the course message board.

  Linux Instructions:

  In Linux, just save rhino.jar to a directory and then set up an alias on your machine so that when you type rhino, the following command will run:

  rlwrap java -jar PATH_TO_RHINO.jar filename
  

  For example, you could edit your Bash startup files and add an alias such as:

  rhino=rlwrap java -jar PATH_TO_RHINO.jar
  

  Or you can set up an exectuable shell script such as the following:

  #!/bin/sh
  rlwrap java -jar /usr/lib/java/rhino.jar $*
  

  If anyone has problems, post a message to the message board or email the instructor and we'll try to figure out what is going on.