title: What JUnit5 jar files are needed? (IntelliJ)
body: <p>TLDR: I'm new to the Java world. How do I know what .jar files to include in my JUnit directory without receiving errors while running my tests?</p>
  <p>So I'm completing a class project have been using the same JUnit5 jars that are found at <a href="https://search.maven.org/search?q=g:org.junit.jupiter%20AND%20v:5.7.0" rel="nofollow noreferrer">https://search.maven.org/search?q=g:org.junit.jupiter%20AND%20v:5.7.0</a> to run my tests. I was recieving an odd error when running some my tests and decided to use the tool that comes with IntelliJ to &quot;add 'JUnit5.4' to the classpath&quot; to see what .jars where pulled in to make it all work. I found that there were a couple discrepancies with what was pulled in using Maven and what existed in the JUnit directory I had been using.</p>
  <p>These are the .jars that I had been using:</p>
  <ul>
  <li>junit-jupiter-5.7.0.jar</li>
  <li>junit-jupiter-api-5.7.0.jar</li>
  <li>junit-jupiter-engine-5.7.0.jar</li>
  <li>junit-jupiter-migrationsupport-5.7.0.jar</li>
  <li>junit-jupiter-params-5.7.0.jar</li>
  </ul>
  <p>This is what was included when I added JUnit5.4 using IntelliJ:</p>
  <ul>
  <li>apiguardian-api-1.0.0.jar</li>
  <li>junit-jupiter-5.4.2.jar</li>
  <li>junit-jupiter-api-5.4.2.jar</li>
  <li>junit-jupiter-engine-5.4.2.jar</li>
  <li>junit-jupiter-params-5.4.2.jar</li>
  <li>junit-platform-commons-1.4.2.jar</li>
  <li>junit-platform-engine-1.4.2.jar</li>
  <li>opentest4j-1.1.1.jar</li>
  </ul>
  <p>Investigating a little further I found that JUnit5 is made up of three &quot;sub-projects&quot; (Jupiter, Vintage, and Platform) but all of these .jar files are not included when I add JUnit through IntelliJ.</p>
  <ol>
  <li>Why are there so many files on the JUnit website that aren't included when I add JUnit using IntelliJ?</li>
  <li>There are files that aren't on the JUnit website that are included when I add through IntelliJ (apiguardian-api-1.0.0.jar and opentest4j-1.1.1.jar). Whats up with that?</li>
  <li>How does IntelliJ determine which .jar files are needed when adding to the classpath? Is it always the same files or will only necessary files be included?</li>
  </ol>
  <p>Like I said earlier I'm new to the Java world so hopefully I'm wording everything correctly.</p>