[java] Add a properties file to IntelliJ's classpath

I'm running a simple Java program from the IntelliJ IDE using the Run->Run menu. It works fine. Now I want to add log4j logging.

I added a resources folder under my project root. I added a log4j.properties file in that folder. I changed the code to log something.

What is the right way to tell IntelliJ to include the resources folder in the classpath so the properties file is seen?

With IntelliJ 8 I could guess like a drunk monkey and eventually get it to work. I have 9 now and I am wholly unsuccessful. I've been trying for an hour. How about an "Add to classpath" option somewhere? /fume /vent /rant

This is one of the dumb mistakes I've done. I spent a lot of time trying to debug this problem and tried all the responses posted above, but in the end, it was one of my many dumb mistakes.

I was using org.apache.logging.log4j.Logger (:fml:) whereas I should have used org.apache.log4j.Logger. Using this correct logger saved my evening.

I spent quite a lot of time figuring out how to do this in Intellij 13x. I apparently never added the properties files to the artifacts that required them, which is a separate step in Intellij. The setup below also works when you have a properties file that is shared by multiple modules.

• Go to your project setup (CTRL + ALT + SHIFT + S)
• In the list, select the module that you want to add one or more properties files to.
• On the right, select the Dependencies tab.
• Click the green plus and select "Jars or directories".
• Now select the folder that contains the property file(s). (I haven't tried including an individual file)
• Intellij will now ask you what the "category" of the selected file is. Choose "classes" (even though they are not).
• Now you must add the properties files to the artifact. Intellij will give you the shortcut shown below. It will show errors in the red part at the bottom and a 'red lightbulb' that when clicked shows you an option to add the files to the artifact. You can also go to the 'artifacts' section and add the files to the artifacts manually.

Actually, you have at least 2 ways to do it, the first way is described by ColinD, you just configure the "resources" folder as Sources folder in IDEA. If the Resource Patterns contains the extension of your resource, then it will be copied to the output directory when you Make the project and output directory is automatically a classpath of your application.

Another common way is to add the "resources" folder to the classpath directly. Go to Project Structure | Modules | Your Module | Dependencies, click Add, Single-Entry Module Library, specify the path to the "resources" folder.

Yet another solution would be to put the log4j.properties file directly under the Source root of your project (in the default package directory). It's the same as the first way except you don't need to add another Source root in the Module Paths settings, the file will be copied to the output directory on Make.

If you want to test with different log4j configurations, it may be easier to specify a custom configuration file directly in the Run/Debug configuration, VM parameters filed like:

-Dlog4j.configuration=file:/c:/log4j.properties.

If you ever end up with the same problem with Scala and SBT:

• Go to Project Structure. The shortcut is (CTRL + ALT + SHIFT + S)

• On the far left list, choose Project Settings > Modules

• On the module list right of that, select the module of your project name (without the build) and choose the sources tab

• In middle, expand the folder that the root of your project for me that's /home/<username>/IdeaProjects/<projectName>

• Look at the Content Root section on the right side, the red paths are directories that you haven't made. You'll want to put the properties file in a Resources directory. So I created src/main/resources and put log4j.properties in it. I believe you can also modify the Content Root to put it wherever you want (I didn't do this).

• I ran my code with a SBT configuration and it found my log4j.properties file.

For those of you who migrate from Eclipse to IntelliJ or the other way around here is a tip when working with property files or other resource files.

Its maddening (cost my a whole evening to find out) but both IDE's work quite different when it comes to looking for resource/propertty files when you want to run locally from your IDE or during debugging. (Packaging to a .jar is also quite different, but thats documented better.)

Suppose you have a relative path referral like this in your code:

new FileInputStream("xxxx.properties");

(which is convenient if you work with env specific .properties files which you don't want to package along with your JAR)

INTELLIJ

(I use 13.1 , but could be valid for more versions)

The file xxxx.properties needs to be at the PARENT dir of the project ROOT in order to be picked up at runtime like this in IntelliJ. (The project ROOT is where the /src folder resides in)

ECLIPSE

Eclipse is just happy when the xxxx.properties file is at the project ROOT itself.

So IntelliJ expects .properties file to be 1 level higher then Eclipse when it is referenced like this !!

This also affects the way you have to execute your code when you have this same line of code ( new FileInputStream("xxxx.properties"); ) in your exported .jar. When you want to be agile and don't want to package the .properties file with your jar you'll have to execute the jar like below in order to reference the .properties file correctly from the command line:

INTELLIJ EXPORTED JAR

java -cp "/path/to_properties_file/:/path/to_jar/some.jar" com.bla.blabla.ClassContainingMainMethod

ECLIPSE EXPORTED JAR

java -jar some.jar

where the Eclipse exported executable jar will just expect the referenced .properties file to be on the same location as where the .jar file is

I have the same problem and it annoys me tremendously!!

I have always thought I was surposed to do as answer 2. That used to work in Intellij 9 (now using 10).

However I figured out that by adding these line to my maven pom file helps:

<build>
  ...
  <resources>
    <resource>
      <directory>src/main/resources</directory>
    </resource>
  </resources>
  ...
</build>

I had a similar problem with a log4j.xml file for a unit test, did all of the above. But figured out it was because I was only re-running a failed test....if I re-run the entire test class the correct file is picked up. This is under Intelli-j 9.0.4

Faced a similar challenge adding files with .ini extensions to the classpath. Found this answer, which is to add it to Preferences -> Compiler -> Resource Patterns -> [...] ;*.ini

Perhaps this is a bit off-topic, seeing as the question has already been answered, but I have experienced a similar problem. In my case only some of the unit test resources were copied to the output folder upon compilation. My persistence.xml in the META-INF folder got copied but nothing else.

In the end I "solved" the problem by renaming the problematic files, rebuiling the project and then changing the file names back to the original ones. Do not ask me why this worked but it did. My best guess is that, somehow, my IntelliJ project had gotten a bit out of sync with the file system and the renaming operation triggered some kind of internal "resource rescan".