Adding Jar files to IntellijIdea classpath

Solution 1:

Go to File-> Project Structure-> Libraries and click green "+" to add the directory folder that has the JARs to CLASSPATH. Everything in that folder will be added to CLASSPATH.

Update:

It's 2018. It's a better idea to use a dependency manager like Maven and externalize your dependencies. Don't add JAR files to your project in a /lib folder anymore.

Solution 2:

If, as I just encountered, you happen to have a jar file listed in the Project Structures->Libraries that is not in your classpath, the correct answer can be found by following the link given by @CrazyCoder above: Look here http://www.jetbrains.com/idea/webhelp/configuring-module-dependencies-and-libraries.html

This says that to add the jar file as a module dependency within the Project Structure dialog:

1. Open Project Structure
2. Select Modules, then click on the module for which you want the dependency
3. Choose the Dependencies tab
4. Click the '+' at the bottom of the page and choose the appropriate way to connect to the library file. If the jar file is already listed in Libraries, then select 'Library'.

Solution 3:

On the Mac version I was getting the error when trying to run JSON-Clojure.json.clj, which is the script to export a database table to JSON. To get it to work I had to download the latest Clojure JAR from http://clojure.org/ and then right-click on PHPStorm app in the Finder and "Show Package Contents". Then go to Contents in there. Then open the lib folder, and see a bunch of .jar files. Copy the clojure-1.8.0.jar file from the unzipped archive I downloaded from clojure.org into the aforementioned lib folder inside the PHPStorm.app/Contents/lib. Restart the app. Now it freaking works.

EDIT: You also have to put the JSR-223 script engine into PHPStorm.app/Contents/lib. It can be built from https://github.com/ato/clojure-jsr223 or downloaded from https://www.dropbox.com/s/jg7s0c41t5ceu7o/clojure-jsr223-1.5.1.jar?dl=0 .