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JUnit 5 - Dynamic Tests Using Streams

[Last Updated: Dec 30, 2025]

Returning a Stream<DynamicTest> enables lazy test generation and integrates naturally with Java stream pipelines.

Example

package com.logicbig.example;

import org.junit.jupiter.api.DynamicTest;
import org.junit.jupiter.api.TestFactory;

import java.util.stream.Stream;

import static org.junit.jupiter.api.Assertions.assertTrue;

public class DynamicTestsUsingStreamsTest {

    @TestFactory
    Stream<DynamicTest> streamBasedTests() {
        return Stream.of(1, 2, 3)
            .map(n -> DynamicTest.dynamicTest("number " + n, () -> assertTrue(n > 0)));
    }
}

Output

$ mvn test -Dtest=DynamicTestsUsingStreamsTest
[INFO] Scanning for projects...
[INFO]
[INFO] ------< com.logicbig.example:junit-5-dynamic-tests-using-streams >------
[INFO] Building junit-5-dynamic-tests-using-streams 1.0-SNAPSHOT
[INFO] from pom.xml
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- resources:3.3.1:resources (default-resources) @ junit-5-dynamic-tests-using-streams ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory D:\example-projects\junit-5\junit-5-dynamic-tests\junit-5-dynamic-tests-using-streams\src\main\resources
[INFO]
[INFO] --- compiler:3.11.0:compile (default-compile) @ junit-5-dynamic-tests-using-streams ---
[INFO] No sources to compile
[INFO]
[INFO] --- resources:3.3.1:testResources (default-testResources) @ junit-5-dynamic-tests-using-streams ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory D:\example-projects\junit-5\junit-5-dynamic-tests\junit-5-dynamic-tests-using-streams\src\test\resources
[INFO]
[INFO] --- compiler:3.11.0:testCompile (default-testCompile) @ junit-5-dynamic-tests-using-streams ---
[INFO] Changes detected - recompiling the module! :source
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 1 source file with javac [debug target 17] to target\test-classes
[INFO]
[INFO] --- surefire:3.5.0:test (default-test) @ junit-5-dynamic-tests-using-streams ---
[INFO] Using auto detected provider org.apache.maven.surefire.junitplatform.JUnitPlatformProvider
[INFO]
[INFO] -------------------------------------------------------
[INFO] T E S T S
[INFO] -------------------------------------------------------
[INFO] +--com.logicbig.example.DynamicTestsUsingStreamsTest - 0.099 ss
[INFO] | +-- [OK] streamBasedTests() number 1 - 0.014 ss
[INFO] | +-- [OK] streamBasedTests() number 2 - 0.003 ss
[INFO] | '-- [OK] streamBasedTests() number 3 - 0.001 ss
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 3, Failures: 0, Errors: 0, Skipped: 0
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.634 s
[INFO] Finished at: 2025-12-27T23:51:56+08:00
[INFO] ------------------------------------------------------------------------

Output Analysis

The output shows that each stream element is transformed into a dynamic test and executed independently, confirming the lazy and scalable nature of stream-based dynamic tests.

Example Project

Dependencies and Technologies Used:

  • junit-jupiter-engine 6.0.1 (Module "junit-jupiter-engine" of JUnit)
     Version Compatibility: 5.0.0 - 6.0.1Version List
    ×

    Version compatibilities of junit-jupiter-engine with this example:

    • 5.0.0
    • 5.0.1
    • 5.0.2
    • 5.0.3
    • 5.1.0
    • 5.1.1
    • 5.2.0
    • 5.3.0
    • 5.3.1
    • 5.3.2
    • 5.4.0
    • 5.4.1
    • 5.4.2
    • 5.5.0
    • 5.5.1
    • 5.5.2
    • 5.6.0
    • 5.6.1
    • 5.6.2
    • 5.6.3
    • 5.7.0
    • 5.7.1
    • 5.7.2
    • 5.8.0
    • 5.8.1
    • 5.8.2
    • 5.9.0
    • 5.9.1
    • 5.9.2
    • 5.9.3
    • 5.10.0
    • 5.10.1
    • 5.10.2
    • 5.10.3
    • 5.10.4
    • 5.10.5
    • 5.11.0
    • 5.11.1
    • 5.11.2
    • 5.11.3
    • 5.11.4
    • 5.12.0
    • 5.12.1
    • 5.12.2
    • 5.13.0
    • 5.13.1
    • 5.13.2
    • 5.13.3
    • 5.13.4
    • 5.14.0
    • 5.14.1
    • 6.0.0
    • 6.0.1

    Versions in green have been tested.

  • JDK 25
  • Maven 3.9.11

JUnit 5 - Dynamic Tests Using Streams Select All Download
  • junit-5-dynamic-tests-using-streams
    • src
      • test
        • java
          • com
            • logicbig
              • example
                • DynamicTestsUsingStreamsTest.java

    See Also