steps:
      - name: Checkout
        uses: actions/checkout@v6

      - name: Install Old JDK 8
        uses: actions/setup-java@v5
        with:
          distribution: 'zulu'
          java-version: 8.0.242

      - name: Configure JDK
        uses: actions/setup-java@v5
        with:
          distribution: 'temurin'
          java-version: 21

    } catch (e: ClassNotFoundException) {
      null
    } catch (e: RuntimeException) {
      // Throws InaccessibleObjectException (added in JDK9) on JDK 17 due to
      // JEP 403 Strongly Encapsulate JDK Internals.
      if (e.javaClass.name != "java.lang.reflect.InaccessibleObjectException") {
        throw e
      }

      null
    }
  }

  /**

 * bugs in OpenJDK 6 or higher.
 *
 * @author Kevin Bourrillion
 */
// TODO(cpovirk): consider renaming this class in light of our now running it under newer JDKs.
@AndroidIncompatible // test-suite builders
public class OpenJdk6MapTests extends TestsForMapsInJavaUtil {
  public static Test suite() {
    return new OpenJdk6MapTests().allTests();
  }

  @Override

  public static void testSubtypeOfStaticAnonymousClass() {
    Class<?> superclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
    assertTrue(TypeToken.of(superclass).isSubtypeOf(superclass));
    assertFalse(
        TypeToken.of(new Mall<Outdoor>().new Shop<Electronics>() {}.getClass())
            .isSubtypeOf(superclass));
  }

 * bugs in OpenJDK 6 or higher.
 *
 * @author Kevin Bourrillion
 */
// TODO(cpovirk): consider renaming this class in light of our now running it under newer JDKs.
@AndroidIncompatible // test-suite builders
public class OpenJdk6MapTests extends TestsForMapsInJavaUtil {
  public static Test suite() {
    return new OpenJdk6MapTests().allTests();
  }

  @Override

 * Contains helper methods for string operations, including backported JDK functionality
 * for compatibility with older Java versions.
 */
public final class StringUtil {

    /**
     *
     */
    private StringUtil() {
    }

    /**
     * Implementation of {@link java.lang.String#join} backported for JDK7.
     *
     * @param delimiter the separator to use between elements

Rene Groeschke <******@****.***> 1622539170 +0200

   * element returned.
   *
   * <p>See <a href="https://bugs.openjdk.org/browse/JDK-6529795">JDK-6529795</a>
   */
  static class IteratorWithJdkBug6529795<T> implements Iterator<T> {
    Iterator<T> iterator;
    boolean nextThrewException;

    IteratorWithJdkBug6529795(Iterator<T> iterator) {
      this.iterator = iterator;
    }

    @Override

    should not use them for communication between trusted and untrusted code.

6.  For the mainline flavor, we test the libraries using OpenJDK 8, 11, and 17
    on Linux, with some additional testing on newer JDKs and on Windows. Some
    features, especially in `com.google.common.io`, may not work correctly in
    non-Linux environments. For the Android flavor, our unit tests also run on
    API level 23 (Marshmallow).

              <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.model=ALL-UNNAMED</arg>
              <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED</arg>
              <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED</arg>
              <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED</arg>
              <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED</arg>