<dependencies> <dependency> <groupId>org.junit.pioneer</groupId> <artifactId>junit-pioneer</artifactId> <version>1.0.0</version> <scope>test</scope> </dependency> </dependencies> import org.junit.jupiter.api.Test; import org.junit.pioneer.jupiter.FreezingTest; import org.junit.pioneer.jupiter.RandomValueSource; import static org.junit.jupiter.api.Assertions.assertEquals; class StringUtilsTest { @Test @FreezingTest void testReverse(@RandomValueSource.StringFixedLength(10) String input) { String reversed = StringUtils.reverse(input); assertEquals(input, StringUtils.reverse(reversed)); } } shell mvn test