final CharMatcher first;
    final CharMatcher second;

    And(CharMatcher a, CharMatcher b) {
      first = checkNotNull(a);
      second = checkNotNull(b);
    }

    @Override
    public boolean matches(char c) {
      return first.matches(c) && second.matches(c);
    }

    @GwtIncompatible // used only from other GwtIncompatible code

    super(ImmutableMap.<Object, ImmutableList<Object>>of(), 0);
  }

  /*
   * TODO(b/242884182): Figure out why this helps produce the same class file when we compile most
   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */
  @Override

    assertTrue(tokL.isSupertypeOf(StringList.class.getGenericInterfaces()[0]));

    @SuppressWarnings("rawtypes") // Trying to test raw class
    TypeToken<Second> tokS = new TypeToken<Second>() {};
    assertTrue(tokS.isSupertypeOf(Second.class));
    assertTrue(tokS.isSupertypeOf(Third.class.getGenericSuperclass()));
  }

  public void testAssignableArrayToClass() {

        assertEquals("Store2", names[1]);
        assertEquals(1, loadCount[0]);

        // Second immediate call should use cache
        names = testFactory.getDataStoreNames();
        assertEquals(2, names.length);
        assertEquals(1, loadCount[0]); // Should not increment

        // Simulate time passing (more than 60 seconds)
        testFactory.lastLoadedTime = System.currentTimeMillis() - 61000L;

        // IOException handling is done by calling code
    }

    /**
     * Compares two SMB files by name.
     * @param f1 first file to compare
     * @param f1name name of first file
     * @param f2 second file to compare
     * @return comparison result for sorting
     * @throws IOException if an I/O error occurs
     */

        assertEquals("Error message", problems.get(0).getMessage(), "First problem should have correct message");
        assertEquals(Problem.Severity.WARNING, problems.get(1).getSeverity(), "Second problem should be WARNING");
    }

        // Arrange: program send() to simulate first, next, next(NO_MORE_FILES)
        List<String[]> batches = new ArrayList<>();
        batches.add(new String[] { ".", "..", "a", "b" }); // first batch, dot entries filtered
        batches.add(new String[] { "c" }); // second batch
        batches.add(new String[] {}); // last -> NO_MORE_FILES

        // send() answer that mutates the provided response

Because this code is executed before the application **starts** taking requests, and right after it **finishes** handling requests, it covers the whole application **lifespan** (the word "lifespan" will be important in a second 😉).

    @Keep public static final WithPublicConstants SECOND = new WithPublicConstants();
  }

  private static class FirstConstantIsNull {
    // To test that null constant is ignored
    @Keep public static final @Nullable FirstConstantIsNull FIRST = null;

    @Keep public static final FirstConstantIsNull SECOND = new FirstConstantIsNull();
  }

  public static class NonFinalFieldIgnored {

  <name>Guava ListenableFuture only</name>
  <description>
    An empty artifact that Guava depends on to signal that it is providing
    ListenableFuture -- but is also available in a second "version" that
    contains com.google.common.util.concurrent.ListenableFuture class, without
    any other Guava classes. The idea is:

    - If users want only ListenableFuture, they depend on listenablefuture-1.0.