What does this symbol mean in IntelliJ? (red circle in the lower left corner of the file name, in it is "J")

Question

In the target folder in IntelliJ for the Java project that I created, I have several java source files in the package. Next to each file, the “J” icon has a red circle with a line through it.

What does it mean? How to fix it?

Answer 1

You need to specify the source directory

File> Project Structure > Modules 

click the directory and click the "Sources" button

This is strange because it is usually done automatically. Perhaps this is better if you re-create the project.

Answer 2

If this is a maven project

• right click on pom.xml
• Add as Maven Project

thank

Answer 3

The first answer from the incontrovertible above that starts with “you need to specify the source of dir” is correct, but I don’t see it telling you an easy way to do this.

Just right-click the java source files folder (for example, "java" in the src / main / java directory if it is a Maven project) and select "Mark directory as> Source Root" (see screenshot below).

Answer 4

This situation occurs when the IDE searches for the src folder and cannot find it in the path. Select the project root (F4 in the windows)> Go to the "Modules on the side tab"> "Select sources"> select the appropriate folder with the source files in it> Click the icon of the blue sources icon (to add sources)> Click the "Green test sources" folder "(to add Unit test folders).

Answer 5

Find all the IntelliJ characters (v15) here: https://www.jetbrains.com/idea/help/symbols.html

This site indicates that this icon means "Java class located from the source root." For more information, see the "Configuring Content Roots" section.

Answer 6

Press F4 in the root directory and select the root source by pressing the source button. He solved my problem!

 for(; ;){ makeGoodCode(); } 

Answer 7

Another option if you use Flavors in Android Studio:

Click Create → Choose Build Option.

In the list, select the option in which you work, and it will turn green, and the rest will have red J.

Answer 8

This means that these files are not part of the project settings.

Answer 9

I downloaded the project from github with a .idea folder. After deleting this folder, everything was in order.

Answer 10

mark the java folder as the root root.It will solve it.

Answer 11

Perhaps your project was not an android project from android studio, please make sure that the “android support” plugin is enabled (Android Studio Settings → Plugins → Choose Android Support)

Answer 12

As mentioned earlier,

1. right click on pom.xml

2. Add as Maven Project

Answer 13

Close Android Studio, delete the .idea and .gradle folders from the project structure and run Studio again.