tester.testAllPublicInstanceMethods(HostSpecifier.fromValid("google.com"));
  }

  private void assertGood(String spec) throws ParseException {
    // Throws exception if not working correctly
    HostSpecifier unused = HostSpecifier.fromValid(spec);
    unused = HostSpecifier.from(spec);
    assertTrue(HostSpecifier.isValid(spec));
  }

  private void assertBad(String spec) {
    try {

  LINE_SEPARATOR("line.separator"),

  /** User's account name. */
  USER_NAME("user.name"),

  /** User's home directory. */
  USER_HOME("user.home"),

  /** User's current working directory. */
  USER_DIR("user.dir");

  private final String key;

  StandardSystemProperty(String key) {
    this.key = key;
  }

  /** Returns the key used to look up this system property. */

### GNU/Linux and macOS

```sh
docker-compose pull

import java.util.concurrent.Future;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicBoolean;
import org.jspecify.annotations.Nullable;

/**
 * Utilities necessary for working with libraries that supply plain {@link Future} instances. Note
 * that, whenever possible, it is strongly preferred to modify those libraries to return {@code
 * ListenableFuture} directly.
 *

        // and that it attempts to create an SmbFile.
        // We cannot directly mock `new SmbFile()`, so we rely on the fact that if it doesn't throw, it's working as expected.

        // This test primarily ensures that the wrapper correctly handles the MalformedURLException
        // and delegates the SmbFile creation.

import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.SortedSet;
import org.jspecify.annotations.Nullable;

/**
 * Provides static utility methods for creating and working with {@link SortedMultiset} instances.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class SortedMultisets {
  private SortedMultisets() {}

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;
import org.jspecify.annotations.Nullable;

/**
 * Provides utility methods for working with resources in the classpath. Note that even though these
 * methods use {@link URL} parameters, they are usually not appropriate for HTTP or other
 * non-classpath resources.
 *
 * @author Chris Nokleberg

Unless the change is a trivial fix such as for a typo, it's generally best to
start by opening a new issue describing the bug or feature you're intending to
fix. Even if you think it's relatively minor, it's helpful to know what people
are working on. And as mentioned above, API changes should be discussed
thoroughly before moving to code.

Some examples of types of pull requests that are immediately helpful:

  - Fixing a bug without changing a public API.

        It's okay if you can't provide complete context on a use case. We understand if you are not
        able to discuss the full details of what you're working on.


        But Guava aims to provide features that are useful across boundaries of projects, companies,
        or even industries — utilities useful for a sizable proportion of all Java programmers

        assertEquals(2, callback.getDocumentSize());
        assertTrue(callback.isCommitted());
    }

    public void test_multiple_datastore_instances() {
        // Test multiple DataStore instances working independently
        final AtomicInteger store1CallCount = new AtomicInteger(0);
        final AtomicInteger store2CallCount = new AtomicInteger(0);

        DataStore dataStore1 = new DataStore() {