How to open and edit multiple projects in the same window? - intellij-idea

I build in maven multiple projects (let's name them A,B,C). Project A uses .jar of project B which uses .jar of project C.
I am modifying the code of all A/B/C projects, (A is MVC app, B are business services and C is some shared layer).
The thing is, in Eclipse/NetBeans I can see all of them at once and it's comfortable to modify them. In IDEA though, I have to open 3 instances (or n instances) of IntelliJ IDEA.
Am I missing something? Is there better approach when using IntelliJ? This is the biggest downside of IntelliJ for me atm.

I think this has improved with recent versions of IntelliJ. In my current version (12.0.2), you can add any number of separate Maven projects to the same "workspace".
The simplest way I've found to do this is to click the little + icon in the "Maven Projects" window (View > Tool Windows > Maven Projects) and then select the additional pom file you want to import.

Step 1: open "Maven Projects"
Step 2: select the project you want to import:

Prequisite
Having all the related projects in the same root directory
can be helpful.
Steps
1) First you create a new Empty project
2) Then you select the root directory of all your projects.
This will create a empty project, with a .idea directory that will simply remember the module organisation we are about to do in the next step
3) Then, in the next window, you import the different projects as modules
4) In the next window, to import each project, simply double click on the build.gradle, or pom.xml
The project will be imported as a new module.
5) Done, you now have all your projects as modules, opened on the same IntelliJ project

Yes, your intuition was good. You shouldn't use three instances of intellij. You can open one Project and add other 'parts' of application as Modules. Add them via project browser, default hotkey is alt+1

In IntelliJ 14.1.2, I did it like following:
Select File->Project Structure->Modules.
Select + and Import Module and select the directory of your project(or directory where pom exists) and click OK.
Follow through the next flow of screens and after you click Finish, you should see the project alongside your existing one.

None of the solutions worked for me, since I am not working on Maven projects. There is a simpler solution. Go to:
File->Project Structure->Modules.
Instead of adding module, simply click the third option (copy). Browse your local directory and select the project you would like to add. Module name will resolve automatically. That's it.
Update: When you want to reopen to project with multiple sub-projects, in order to avoid re-doing steps as described above, just go to
File->Open Recent->'Your Big Project'.

Since macOS Big Sur and IntelliJ IDEA 2020.3.2 you can use "open projects in tabs on macOS Big Sur" feature. To use it, you have to enable this feature in your system settings:
System Preferences -> General -> Prefer tabs [always] when opening documents
After this step, when you will try to open second project in IntelliJ, choose New Window (yes, New Window, not This Window).
It should result with opening new project in same window, but in the new card:

To expand #Neo answer:
after choosing your directory. select import module from external model and choose your model (maven in this case).
Then check keep project files option from next dialog. It will keep all files in original directory.
Your final project structure would be something like this.
Now you can add your module as dependency to other module's pom.xml and if you change the source code of your dependencies, Intellij takes care of updating your project (there is no need to run mvn build manually for dependencies)

new empty project
File -> New -> Module from Existing Sources

For who uses Gradle can also avail the same:
Go to:
1. View --> Tool Windows --> Gradle
2. Click on the + button and add your build.gradle file

Open preference -> appearance & behaviour -> System settings -> select (open project in new window) then apply.
Then you could open and edit multiple projects.

You can use Armory plugin which makes switching between projects comfortable. The default shortcut for Project List is Alt + A.
By default currently opened projects are displayed at the top of this list (with bold style).

Use the button for the add maven projects and go inside the folder of the project. Then, select the pom.xml file and add them in the IntelliJ.

Press "F4" on windows which will open up "Project Structure" and then click "+" icon or "Alt + Insert" to select a new project to be imported; then click OK button...

To Intellij IDEA 2019.2, F4 + click on module, click to + for add any project from your HDD, above this menu yo can edit the IDE with you create the project and more options, very easy

For people not using maven to build and wanting to add a new project (I am using intellij 14.1.3):
Right click the top level folder in the project view, select new ->
Module
Name the module the same name as the project to be added
From the top menu select File->New->Project. Enter the same name as
the new module, same folder locations as well.
Open the Project, and wait for intellij to create the project
structure.
Close this new project, and open the original project the module was
added to in step 2
Depending on your builder, additional steps will be needed to add it to the build process.
For SBT, and in the top level project I modified the Build.scala file to aggregate the new project, and added the project in the SBT projects window. More info on SBT multiproject builds: http://www.scala-sbt.org/0.12.2/docs/Getting-Started/Multi-Project.html

"IntelliJ IDEA 2022.1.1 (Community Edition)" you have to navigate
To Add Exiting Module to same window navigate "File -> New -> Module from Existing Sources" then it will allow you to select pom.xml and then click "Create" button next window then project will be added to your current workspace.
Note :: Who ever switches from Eclipse to Intellij this is the first problem

Assuming they are under the same folder, click File-Open File or Project-<parent folder>.

you can use import module option which will open it just like eclipse in the same navigator.

For IntelliJ Idea 2021.3.3 users, The below solution didn't work for me, although I was selecting my project main folder, I've gotten only the main and test folders imported!
Peoject Structure => Modules => Import module
The solution is:
view => tool Windows => Maven => click the + icon => add the project POM.xml file

I am new to maven and did not understand how I could work with local maven project added through Viktor Nordling's answer and still have a proper dependency in pom.xml file. The answer is simple: intellij first looks at your locally added module and if it doesn't find one it goes to get the project remotely. You can check this by looking at "external libraries" under your project browser when you add or remove maven module.
Hope this helps anyone.

As of release 2019.2, this is as easy as File->Attach Project.
🎉🎉🎉🎉🎉
See: https://youtrack.jetbrains.com/issue/WEB-7968

After importing project into IntelliJ, Go to pom.xml of each module -> right click -> Click on Add as Moven Project. It will add the module as Moven project, do this for all the modules in the Project. Refer this

Related

Command line generation of IntelliJ IDEA project files?

I prefer having one IDEA project per task I'm working on. If it's a Gradle project, I can run gradlew idea to generate the project files then rename them to be indicative of the task I'm working on (so that when re-opening from IDEA a project, it's obvious what the task is and IDEA is able to list several tasks for the same Gradle project). This works well enough if it's a Gradle project, but if it's not, I'm left with using the IDEA GUI to open the project by pointing to the working directory. Is there a command-line way to generate the IDEA project files so I can rename them prior to using the GUI? Being able to do this would also obviate the need for using gradlew idea for this purpose.
Using the GUI, create the project by pointing it to the build.gradle file or project root directory. Once the project is created:
click the File menu
click the Project Structure menu item
change the Project name text value

What is root-build in intellij?

Whenever I create an sbt project in intellij, I get something like this:
What is root-build here, and why is it labeled as "sources root"?
When you create an sbt project in IntelliJ, the default root of sbt, called root, is added as a module. You can see this by right-clicking on the project and clicking Open Module Settings. That is what root-build refers to.
You can read a description of content roots on the IDEA site.
I'm just guessing (at least I am being honest) but I believe SBT configuration itself can be considered a "development project" and so is setup as a separate module called "project" for its build, i.e. the build of the build configuration. Notice it has its own "target" directory.

What is the command line option to pass into the activator framework to generate an intellij project?

I'd like to generate the intellij project files from a typesafe activator project via a script - is there a command line interface or command i can use for this purpose?
(i wasn't able to find directions for one online, or in the usual help locations)
Please note that since IntelliJ IDEA version 13 it is no longer necessary to generate files for IntelliJ IDEA. sbt support is now build in, you can open/import the project by opening your build.sbt with IntelliJ IDEA: http://blog.jetbrains.com/scala/2013/11/18/built-in-sbt-support-in-intellij-idea-13/
Remember that Activator is just an sbt wrapper with optional UI mode. So what you want is sbt-idea:
https://github.com/mpeltonen/sbt-idea
The Activator UI will auto-add this plugin and then (on the Code tab) it has an "open in" menu item to generate the intellij project.
If you want to script it, there are two steps:
add the plugin (either drop an idea.sbt in project/ directory or put it globally in ~/.sbt/0.13/plugins)
run activator gen-idea

How to see java files in project tree in intellij idea?

I'm working with intellij idea but I can't see the java source files in the project tree. I see the packages, I can open it, but the class files are not displayed. Any idea? This has worked until a few days ago...
Under the intelliJ IDEA 14.0.3 community edition, upon launch I don't see my project folders. I found by going into
View > Tool Windows > Project
seems to show the folder structure.. Same as ALT + 1
Below the menubar , on the left there is a dropdown which in your case may be showing "packages" now (because you can see the packages). From the same dropdown, select "Project Files" below "SCOPES"
You need to check out the project correctly if you are checking out from SVN repo or you must not have selected correct project folder.
You can also configure your project from File->Project Structure check your Source folder is excluded or not.
Also Alt+1 will give you project structure of files in tree format
Check in "Project Structure" (ctrl+alt+shift+S) if you didn't set your source as "Excluded" (in Modules, sources).
If you are develop a maven project, you could run mvn idea:idea and then open the project in your Intellij, the source files and the project tree would become the shape you like.

In Intellij, right click on a test does not present a "Run" option

In IntelliJ when I right click on a test I dont see a "Run ClassX or MethodY" anymore. In fact there is no "run" window and when I right click I cannot run any class.
It was all working fine about 3 hours ago so I am not quite sure what has changed.
IntelliJ 10.5.1 (Licensed and NOT community edition)
Java 1.6.0_24
This happens for all projects.
Update 1
I installed IDEA 11 and imported settings from 10 and then saw that it was not a free upgrade close IDEA 11 and started using IDEA 10. I am fairly certain things stopped working from that point but not sure. Is that a problem? Can I somehow delete IntelliJ configuration directory somehow and restart?
Adding a screenshot when I don't get Run option on right click:
My problem was that my test class wasn't public. I needed:
public class MyTest {
#Test
public void testMethod() {
instead of:
class MyTest {
#Test
void testMethod() {
If your project is a maven project then you can just right-click on the pom.xml file and select "add as Maven project".
This approach worked for me. (green plus third from the bottom)
I had the same problem. To fix it, I had to ensure that my class had a proper main method:
public static void main(String[] args) {
}
Every keyword in the above statement is critical. If you omit one, IntelliJ wont' recognize it. Easy-to-forget keywords are static, void, and the String[] args argument.
I had forgotten the arguments in mine ;-)
Also make sure your source code is inside a src folder which is marked as such by IntelliJ.
In my case, the cause was disabled JUnit plugin. (File — Settings — Plugins — JUnit, check, OK)
If you're using JUnit 5 (Jupiter), this happens when you use the old #Test annotation from JUnit 4. Just replace
import org.junit.Test;
with
import org.junit.jupiter.api.Test;
and IntelliJ should show the "Run" button again.
Ok after tremendous amount of eyeballing I located a {HOME}/.java directory which seemed to contain some Jetbrains related preferences. I deleted that directory plus {HOME}/.IntelliJ* directories. Then deleted all my intellij installations and downloaded it again from scratch and it now works fine..
Sigh....
Disabling gradle plugin solved the issue for me (community edition 2018.2)
In my case i right clicked the src folder and went to -> mark directory as -> sources root.
I had the same problem. I solve it by
File -> Invalidate Caches / Restart
right click on the top pom.xml -> Maven -> reimport
There should be no need to delete any configuration files.
I found that I used to have the Run option in the context menu to select either run tests or run Scala tests, etc. After I had selected an option for the first time, my options were no longer there.
I was able to resolve this issue and select the type of tests I wanted for that folder by creating a Run/Debug configuration following the instructions found in the documentation here...
https://www.jetbrains.com/help/idea/2016.1/creating-run-debug-configuration-for-tests.html?origin=old_help
As i had the same issue , i could clearly See that #Test is not providing any hint when i press control key and hover , and the same was confirmed as External Libraries was not having Gradle Dependencies added so i had to update the project as gradle project suggested by a pop up when you start Intellij.
I could resolve the issue by disabling the Gradle plugin from the Plugin menu and restart.
If the project is already added as a Maven one, unlink it.
right click on the project -> Maven -> Unlink Maven Projects
Then link it again:
right click on pom.xml -> + Add as Maven Project
I've just had the same problem and solved it in the following way.
Go to your $USER/$INTELLIJ directory e.g. $USER/.IdeaC2018.3 then find config/plugins. Rename the plugins directory and restart IntelliJ.
My guess is that the problem was caused when I upgraded IntelliJ and incompatibilities with the cucumber plugin.
For me this happened after updating Idea, and then updating all Plugins. Apparently Idea had not restarted yet. Going to File -> Settings -> Plugins and clicking 'Restart Idea' solved the problem
if you can see the play button in left side of the main function then click right click and press run.
in my case, I did not have an output folder.
file -> project structure -> under 'project' tab there's 'Project compiler output' -> define your folder.
Unfortunately, none of these worked for me. I had to
'File' -> "Invalidate Caches / Restart"
Click on pom.xml file, and then 'maven' -> "Generate Sources"
Search for pom.xml file --> Right Click on pom.xml --> Click on Add as Maven Project.
You should get a pop-up, saying downloading Mavin Plugin.
Wait till it gets completed. It takes some time depending on the number of content in pom.xml.
In the below screenshot, "BackendApp.java" is Driver Java file that contains
public static void main(String[] args){}
Right Click on such driver java file and you see Run option in green color.
I had this problem with a Kotlin project. Following action solved it:
right click on test folder -> select Mark Directory as -> choose Test Sources Root
So I had this problem on pycharm and the problem was that there was already a run configuration (in the dropdown next to the play button) that had the name of the file. When i deleted that run configuration it would create a new one that was correct.
I had the same problem and I tried all the above solutions nothing worked for me but after I install TestNG plugin it's started working since there are some TestNG annotations used in my unit tests
I had the same problem on my Intellij 2019.3 after that I updated from 2019.2.4. I thought that the problem came from the updated first, but the rollback didn't fix, so I tried de solution above e the problem was fixed. After configuring all my projects from scratch the problem get back, so I started to check everything I did. I discovered that an old project from Eclipse that uses files .launch to run and need some plugins to be able to execute on Intellij was causing the problem, after disable the following plugins the test option return.
In my case, my project is using Bazel.
The solution was to sync Bazel from Bazel plugin.
Since this is a top Google result when trying to figure out how to run a Scala project, and since for some reason IntelliJ (I'm on 2020.1.2) doesn't automatically create a run configuration for a Scala project (in contrary to a Java project), it's worth laying out the basics for future readers:
Click on "Edit Configuration" on the top right of the screen.
Inside the opened window, click the + button its top left.
Choose "Application".
Now, let's go through the required fields:
in the "Name" field, enter a name for this configuration, e.g. "run".
in the "Main Class" field, enter your main class name.
Alternatively, use the ... button to the left: inside the window that opens, click the "Project" tab, navigate to your main class, pick it and click "ok".
Note: If your main class doesn't have a main method, IntelliJ would show an alert. see listing 9 below.
Make sure the value in "Working Directory" field is correct (it should be the project folder).
in "Use classpath of module", select your module (see project vs module in IntelliJ)
That's it for configuring. Click "Apply", and close the window. Here's an example final result:
Note that my Main class is part of a package named Demo, but having a package is not necessary.
Inside the main class, make sure there's a main method.
See #Josiah Yoder answer for java, and for Scala it's:
def main(args: Array[String]): Unit = {
}
That's it. You should now have the green run and debug buttons enabled.
Seems there are version conflicts between plugins and IDEA itself that commonly break this functionality. Many of the solution here indicate people manually trying to identify the plug in, I found that to be impossible. So here is a generic way, without having to uninstall IDEA as one solution proposed:
File > Settings > Plugins > gear icon > disable all downloaded plugins
This fixed it for me.
Make sure the method is not static! JUnit only allows #Test before instance methods but Intellij doesn't complain even if you use #Test above a static method.