*       be reusable, and operations that read from the stream (including {@link #size()}, in some
 *       implementations) will prevent further operations from completing as expected.
 * </ul>
 *
 * @since 14.0
 * @author Colin Decker
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class ByteSource {

  /** Constructor for use by subclasses. */
  protected ByteSource() {}

  /**

import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Provides utility methods for working with byte arrays and I/O streams.
 *
 * @author Chris Nokleberg
 * @author Colin Decker
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class ByteStreams {

  private static final int BUFFER_SIZE = 8192;

 * Interface for a supplier of streams that can report whether a stream was opened and whether that
 * stream was closed. Intended for use in a test where only a single stream should be opened and
 * possibly closed.
 *
 * @author Colin Decker
 */
public interface TestStreamSupplier {

  /** Returns whether or not a new stream was opened. */
  boolean wasStreamOpened();

  /** Returns whether or not an open stream was closed. */

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.Multimap;

/**
 * Helper methods/assertions for use with {@code com.google.common.collect} types.
 *
 * @author Colin Decker
 */
@GwtCompatible
final class GoogleHelpers {

  private GoogleHelpers() {}

  static void assertEmpty(Multimap<?, ?> multimap) {
    if (!multimap.isEmpty()) {

import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;

/**
 * A char source for testing that has configurable options.
 *
 * @author Colin Decker
 */
public class TestCharSource extends CharSource implements TestStreamSupplier {

  private final TestByteSource byteSource;

  public TestCharSource(String content, TestOption... options) {

import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
import junit.framework.TestCase;

/**
 * Tests for {@link AbstractListeningExecutorService}.
 *
 * @author Colin Decker
 */
public class AbstractListeningExecutorServiceTest extends TestCase {

  public void testSubmit() throws Exception {
    /*
     * Mostly just tests that TrustedListenableFutureTask are created and run; tests for

import static com.google.common.hash.Hashing.ChecksumType.CRC_32;

import java.util.zip.Checksum;
import junit.framework.TestCase;

/**
 * Tests for ChecksumHashFunction.
 *
 * @author Colin Decker
 */
public class ChecksumHashFunctionTest extends TestCase {

  public void testCrc32_equalsChecksumValue() throws Exception {
    assertChecksum(CRC_32, "");
    assertChecksum(CRC_32, "Z");

 * Generates tests of all methods on a {@code ByteSink} given various inputs written to it as well
 * as sub-suites for testing the {@code CharSink} view in the same way.
 *
 * @author Colin Decker
 */
@AndroidIncompatible // TODO(b/230620681): Make this available (even though we won't run it).
public class ByteSinkTester extends SourceSinkTester<ByteSink, byte[], ByteSinkFactory> {

import java.nio.ByteOrder;

/**
 * Abstract {@link Hasher} that handles converting primitives to bytes using a scratch {@code
 * ByteBuffer} and streams all bytes to a sink to compute the hash.
 *
 * @author Colin Decker
 */
@ElementTypesAreNonnullByDefault
abstract class AbstractByteHasher extends AbstractHasher {
  private final ByteBuffer scratch = ByteBuffer.allocate(8).order(ByteOrder.LITTLE_ENDIAN);

import static org.junit.Assert.assertThrows;

import java.io.ByteArrayOutputStream;
import java.util.Random;
import junit.framework.TestCase;

/**
 * Tests for AbstractByteHasher.
 *
 * @author Colin Decker
 */
public class AbstractByteHasherTest extends TestCase {

  public void testBytes() {
    TestHasher hasher = new TestHasher(); // byte order insignificant here
    byte[] expected = {1, 2, 3, 4, 5, 6, 7, 8};