I'm trying to run JUnit tests in Visual Studio Code without using Maven or Gradle, just using plain .java files and .jar libraries.

Project Setup:

I'm using VS Code with the Java Extension Pack, and I added the following to .vscode/settings.json:

{
  "java.project.sourcePaths": [
    "src/main/java",
    "src/test/java"
  ],
  "java.project.outputPath": "bin",
  "java.project.referencedLibraries": [
    "lib/**/*.jar"
  ]
}

Inside the lib/ folder, I placed:

junit-4.13.2.jar

hamcrest-core-1.3.jarTestHello/
├── lib/
│   ├── junit-4.13.2.jar
│   └── hamcrest-core-1.3.jar
├── src/
│   ├── main/java/ExceptionTest/MessageUtil.java
│   └── test/java/ExceptionTest/TestJunit.java
├── .vscode/settings.json

What worked initially:

The first time I wrote my test, I just: Created .java files manually in a folder, Clicked on the Testing tab in the left sidebar, VS Code asked me to enable "Java Testing", and I accepted. It worked! I saw the green triangle "Run Test" icons next to my test methods.

The problem:

After closing and reopening VS Code later, now: When I click on the Testing panel, it says: "No tests found". The test annotations like @Test, @Before, and Assert are underlined with errors: The import .junit cannot be resolved, Test cannot be resolved to a type, Assert cannot be resolved. The green triangle icons (Run Test) have disappeared from the gutter

My test class (TestJunit.java):

package ExceptionTest;

import .junit.Test;
import static .junit.Assert.assertEquals;

public class TestJunit {

    String message = "Robert";
    MessageUtil messageUtil = new MessageUtil(message);

    @Test
    public void testSalutationMessage() {
        message = "Hi!" + "Robert";
        assertEquals(message, messageUtil.salutationMessage());
    }
}

Question: How can I make VS Code persistently recognize and run JUnit tests without Maven or Gradle? Why did the tests disappear after restarting VS Code? Is there a way to force VS Code to re-scan and show the test icons again?

I'm trying to run JUnit tests in Visual Studio Code without using Maven or Gradle, just using plain .java files and .jar libraries.

Project Setup:

I'm using VS Code with the Java Extension Pack, and I added the following to .vscode/settings.json:

{
  "java.project.sourcePaths": [
    "src/main/java",
    "src/test/java"
  ],
  "java.project.outputPath": "bin",
  "java.project.referencedLibraries": [
    "lib/**/*.jar"
  ]
}

Inside the lib/ folder, I placed:

junit-4.13.2.jar

hamcrest-core-1.3.jarTestHello/
├── lib/
│   ├── junit-4.13.2.jar
│   └── hamcrest-core-1.3.jar
├── src/
│   ├── main/java/ExceptionTest/MessageUtil.java
│   └── test/java/ExceptionTest/TestJunit.java
├── .vscode/settings.json

What worked initially:

The first time I wrote my test, I just: Created .java files manually in a folder, Clicked on the Testing tab in the left sidebar, VS Code asked me to enable "Java Testing", and I accepted. It worked! I saw the green triangle "Run Test" icons next to my test methods.

The problem:

After closing and reopening VS Code later, now: When I click on the Testing panel, it says: "No tests found". The test annotations like @Test, @Before, and Assert are underlined with errors: The import .junit cannot be resolved, Test cannot be resolved to a type, Assert cannot be resolved. The green triangle icons (Run Test) have disappeared from the gutter

My test class (TestJunit.java):

package ExceptionTest;

import .junit.Test;
import static .junit.Assert.assertEquals;

public class TestJunit {

    String message = "Robert";
    MessageUtil messageUtil = new MessageUtil(message);

    @Test
    public void testSalutationMessage() {
        message = "Hi!" + "Robert";
        assertEquals(message, messageUtil.salutationMessage());
    }
}

Question: How can I make VS Code persistently recognize and run JUnit tests without Maven or Gradle? Why did the tests disappear after restarting VS Code? Is there a way to force VS Code to re-scan and show the test icons again?

• java
• visual-studio-code
• junit
• classpath

1 Answer 1

I tested your project and there is no problem. This may be caused by cache. To re-scan, click Java Projects panel -> three dots (more action) -> clean workspace. Then prompt a warning message window -> reload and delete.