Intellij Cannot resolve symbol on import
JavaIntellij IdeaImportClasspathJava Problem Overview
This problem happens intermittently for different libraries and different projects. When trying to import a library, the package will be recognized, but the class name can't be resolved.
If on the import statement, I right-click -> Goto -> the package's declaration
, I see all the decompiled classes displayed in the side pane -- Including the ones I need --
If I try to auto-complete the import statement, I notice the class I need is not featured in the dropdown.
I tried invalidating caches already, doesn't work. I cannot find any class conflicts -- there is no other jar file in my classpath with the same package name. I am able to import this class into other projects.
Please see screen shots:
Anyone have a clue?
Java Solutions
Solution 1 - Java
You can try invalidating the cache and restarting IntelliJ, in many cases it will help.
File -> Invalidate Caches/Restart
Solution 2 - Java
There can be multiple reasons for this. In my case it was wrong source root issue. Invalidate caches didn't work along with other solutions.
Check your module source roots.
-
Project Structure (Ctrl+Alt+Shift+S).
-
Modules
-
Select your problem module.
-
Change tab on top of window "Sources".
-
Remove unwanted source roots. Keep one and add src and test source roots in this root.
Solution 3 - Java
File
-> Invalidate Caches/Restart
And
Build your project
Solution 4 - Java
IntelliJ has issues in resolving the dependencies. Try the following:
- Right click on pom.xml -> Maven -> Reimport
- Again Right click on pom.xml -> Maven -> Generate sources and update folders
Solution 5 - Java
Run this command in your project console:
mvn idea:idea
Done. Had this issue many times. Tried 'Invalidate Cache & Restart' and all other solutions. Running that command works perfect to me. I'm currently using IntelliJ 2019.2, but this also happened in previous versions and solution worked as well.
Solution 6 - Java
Check your module dependencies.
- Project Structure (Ctrl+Alt+Shift+S).
- Modules
- Select your problem module.
- Change tab on top of window "Dependencies".
- Check what needed library (maybe, you need to add specified library in the tab 'libraries') or module has listed here and it has right scope ('complile' mostly).
Solution 7 - Java
I faced a similar issue, Mike's comment helped me move in the direction to solve it.
Though the required library was a part of the module in my project too, it needed a change of scope. In the module dependency, I changed the scope to "Compile" rather than "Test" and it works fine for me now.
Solution 8 - Java
File -> Invalidate Caches/Restart or rebuilding the project did not work wor me.
What worked for my Gradle project was to "Refresh all Gradle projects" from the Gradle tab on top-right corner of IntelliJ v2017, using the yellow marked button shown below:
Solution 9 - Java
Had the same problem till I noticed that the src folder was marked as root source instead of java! Changing to only the java (src/main/java) to be the source root solved my problem
Solution 10 - Java
I found the following answer from @jossef-harush and @matt-leidholm useful from another link
- in IntelliJ editor, click on the red keyword (
Integer
for example) and press ALT + ENTER (or click the light bulb icon) - select
Setup JDK
from the intentions menu
- click on
Configure
- In my case, the
JDK
path was incorrect (pointed on/opt/jdk1.7.0_51
instead of/opt/jdk1.7.0_65
)
- click on the ... and browse to the right
JDK
path
- let's clear the cache
Solution 11 - Java
Right click on pom.xml file, go to Maven click on Reimport. I had similar problem and this worked for me.
Solution 12 - Java
After a long search, I discovered that a dependency was somehow corrupted on my machine in a maven project. The strange thing was that the dependency was still working correctly in the compiled java code. When I cleaned and rebuilt my maven dependency cache however, the problem went away and IntelliJ recognized the package. You can do this by running:
mvn dependency:purge-local-repository
Intrestingly, the source of my problem hence wasn't IntelliJ, but maven itself.
Solution 13 - Java
For 2020.1.4 Ultimate edition, I had to do the following
View -> Maven -> Generate Sources and Update Folders For all Projects
The issue for me was the libraries were not getting populated with
mvn -U clean install
from the terminal.
Solution 14 - Java
Try cleaning maven from upstream by:
mvn -U clean install
Solution 15 - Java
I also got this error for multiple times when I try to build a new java project.
Below is the step how I got this stupid issue.
- Create an empty project, and create new directory
src/main/java
. - Create the source package
net.gongmingqm10.sketch
. - Use
gradle wrapper
,gradle idea
to build the gradle stuff for the project. - Add some dependencies in
build.gradle
file, andgradle build
, reimport the project. - Create
User.java
andSchool.java
in the existing packagenet.gongmingqm10.sketch
- I got the error while I try to use import School in User.java.
- Intellij keeps complain can not resolve symbol on import.
Solution:
Build the project first, and mark the main/java as the source root. Create a new directory with the same name net.gongmingqm10.sketch
. Move all the files from the old troubling packages to new package.
Root cause:
As you can see from the tree. I got a directory named net.gongmingqm10.sketch
. But what we really need is the 3 levels directory: net->gongmingqm10->sketch
But before I finish building my project in Intellij, I create new directory named net.gongmingqm19.sketch
, which will give me a real directory with the name net.gongmingqm10.sketch
.
When we trying to import it. Obviously, how can intellij import the file under the weired directory with the name a.b.c
.
Solution 16 - Java
@Anton Dozortsev I was driven crazy by a similar behavior; I ended up re-installing the IDE a bunch of times, only getting past the issue after removing the IDEA app, all caches, preferences, etc.
I tried all kinds of steps in the interim, (like restarts, invalidations, deleting .idea
and *.iml
files, and others.)
Turns out, the problem was due to IntelliJ's idea.max.intellisense.filesize
setting. I had set it to 100KB, which was smaller than my dependency's size, leading to IntelliJ showing it as unknown, just like in your screenshot.
Fix:
-
Click on Help -> Edit Custom Properties
-
Set the property to a larger value; the default is 2500KB
idea.max.intellisense.filesize=2500
Solution 17 - Java
Please try File-> Synchronize. Then close and reopen IntelliJ before you invalidate.
Once I restarted. I would have invalidated but the synchronize cleared everything after restarting.
Solution 18 - Java
Simple Restart worked for me.
I would suggest first try with restart and then you may opt for invalidating the cache.
PS : Cleaning out the system caches will result in clearing the local history.
Solution 19 - Java
I found the source cause!
In my case, I add a jar file include some java source file, but I think the java source is bad, in Intellij Idea dependency library it add the source automatic, so in Editor the import is BAD, JUST remove the source code in "Project Structure" -> "Library", it works for me.
Solution 20 - Java
What did it for me is to edit the package file in the .idea folder as I accidentally added sources to this jar library and android couldn't resolve it by deleting the sources line as marked in the b/m picture library error.
Then rebuild the gradle and bam problem solved.
Solution 21 - Java
I had the same issue and the reason for that was incorrect marking of the project's sources.
I manually created the Root Content and didn't notice that src/main/test
folder was marked as Sources
instead of Tests
. So that is why my test classes were assumed to have all their test libraries (JUnit
, Mockito
, etc.) with the scope of Compile, not Test.
As soon as I marked src/main/test
as Tests and rebuilt the module all errors were gone.
Solution 22 - Java
I had this recently while trying to use Intellij to work on NiFi, turned out the issue was that NiFi requires Maven >= 3.1.0 and the version that I'd checked out with (I guess my default) was 3.0.5. Updating the Maven version for the project fixed it, so in some cases Maven version mis-alignment can be a thing to look...I'd guess it's fairly unusual but if you get this far on the thread you're probably having an unusual issue :)
Solution 23 - Java
file
-> Project Structure
-> Modules
, find the module with problems, click it and choose the Dependencies
tab in the right side. Click the green plus sign, try to add the jar or libraries that cause the problem. That works for me.
Solution 24 - Java
Nothing I tried above worked for me (not that I tried every suggestion). What finally did the trick was to rename the class -- I just added a 2 to the class name and filename. Then I resolved all the references manually. (Since they weren't recognized, the refactoring did not change the references automatically.)
Once the "2-version" was happily resolved everywhere, I was then able to refactor and remove the 2 from the class and file, and everything was then as it should be.
Solution 25 - Java
in my case the solution was to add the project as maven project, besides the fact that i imported as maven project :P
go to pom.xml -> right click -> add as maven project
Solution 26 - Java
My issue was my Maven plugin got disabled after an update. I went to Help -> Find Action... -> Typed in Maven and found that it was "Off". I clicked the toggle switch and after a bit of loading it was re-enabled.
Solution 27 - Java
Also, check your class is not in compile exclusions
If you see, that there is a little grey cross in left top corner, you must remove class from compile exclusions
How to remove
Solution 28 - Java
Old question, '21 response. I ran into the issue where my go build
would build code successfully but my Goland IDE showed missing modules or dependencies. I tried Invalidating Caches and Restart, but had the same problem. From another S/O thread, I tried adding the GO111MODULE=on to my Path Variables, but that didn't resolve the IDE problems either.
What worked for me was picking the correct GOROOT path in Preferences
> Go
> GOROOT
.
I had two versions of go installed, one by brew and one from the online Go installer. I selected the brew install path, and my IDE was able to resolve the dependencies properly.
Solution 29 - Java
I've tried all the complicated methods and they didn't work, since I was too lazy to re-import the project I tried something else. Mine is a gradle project, so I went to my gradle.build file, removed the dependency, refreshed the dependencies, then added the dependency again and refreshed again, the imports started working after that.
Solution 30 - Java
Faced similar issue, I Updated Intellij and error start coming - Can't Resolve Symbols.
Went to Plugins, Updated the plugins & Restart Problem Solved !!
Solution 31 - Java
I had a similar issue with my imported Maven project. In one module, it cannot resolve symbol on import for part of the other module (yes, part of that module can be resolved).
I changed "Maven home directory" to a newer version solved my issue.
Update: Good for 1 hour, back to broken status...