JetBrains [is working on][kotlin_sams] SAM conversions of Kotlin interfaces. Expect it in a future
release of the Kotlin language.


Companion Imports
-----------------

The equivalent of static methods in Java is companion object functions in Kotlin. The bytecode is
the same but `.kt` files now need `Companion` in the import.

This works with OkHttp 3.x:

```kotlin

    /**
     * Returns {@code true} if there is at least one problem collected with severity equal or more severe than
     * {@link org.apache.maven.api.services.BuilderProblem.Severity#WARNING}. This check is logically equivalent
     * to "is there any problem reported?", given warning is the lowest severity.
     */
    default boolean hasWarningProblems() {
        return hasProblemsFor(BuilderProblem.Severity.WARNING);
    }

    /**

    *   tf.data service now supports auto-sharding. Users specify the sharding
        policy with `tf.data.experimental.service.ShardingPolicy` enum. It can
        be one of `OFF` (equivalent to today's `"parallel_epochs"` mode),
        `DYNAMIC` (equivalent to today's `"distributed_epoch"` mode), or one of
        the static sharding policies: `FILE`, `DATA`, `FILE_OR_DATA`, or `HINT`

    CharSource concatenated = CharSource.concat(cycle);

    String expected = "abcdabcd";

    // read the first 8 chars manually, since there's no equivalent to ByteSource.slice
    // TODO(cgdecker): Add CharSource.slice?
    StringBuilder builder = new StringBuilder();
    Reader reader = concatenated.openStream(); // no need to worry about closing

	// The extended form begins with \\?\, as in
	// \\?\c:\windows\foo.txt or \\?\UNC\server\share\foo.txt.
	// The extended form disables evaluation of . and .. path
	// elements and disables the interpretation of / as equivalent
	// to \. The conversion here rewrites / to \ and elides
	// . elements as well as trailing or duplicate separators. For
	// simplicity it avoids the conversion entirely for relative

     */
    public String getPassword() {
        return password;
    }

    /**
     * Return the domain and username in the format:
     * {@code domain\\username}. This is equivalent to {@code toString()}.
     */
    @Override
    public String getName() {
        final boolean d = domain.length() > 0 && !domain.equals("?");
        return d ? domain + "\\" + username : username;
    }

    // hashcodes from non-overlapping hash computations
    HashCode expected1 = randomHash(hashFunction, new Random(1L), numActions);
    HashCode expected2 = randomHash(hashFunction, new Random(2L), numActions);

    // equivalent, but overlapping, computations (should produce the same results as above)
    Random random1 = new Random(1L);
    Random random2 = new Random(2L);
    Hasher hasher1 = hashFunction.newHasher();

  }

  /**
   * Waits until the given weak reference is cleared, invoking the garbage collector as necessary to
   * try to ensure that this will happen.
   *
   * <p>This is a convenience method, equivalent to:
   *
   * {@snippet :
   * awaitDone(new FinalizationPredicate() {
   *   public boolean isDone() {
   *     return ref.get() == null;
   *   }
   * });
   * }
   *

    // initial capacity / concurrency level
    assertEquals(16 / map.segments.length, map.segments[0].table.length());
  }

  public void testSetKeyEquivalence() {
    Equivalence<Object> testEquivalence =
        new Equivalence<Object>() {
          @Override
          protected boolean doEquivalent(Object a, Object b) {
            return false;
          }

          @Override

    // initial capacity / concurrency level
    assertEquals(16 / map.segments.length, map.segments[0].table.length());
  }

  public void testSetKeyEquivalence() {
    Equivalence<Object> testEquivalence =
        new Equivalence<Object>() {
          @Override
          protected boolean doEquivalent(Object a, Object b) {
            return false;
          }

          @Override