@ElementTypesAreNonnullByDefault
public abstract class Ticker {
  /** Constructor for use by subclasses. */
  protected Ticker() {}

  /** Returns the number of nanoseconds elapsed since this ticker's fixed point of reference. */
  public abstract long read();

  /**
   * A ticker that reads the current time using {@link System#nanoTime}.
   *
   * @since 10.0
   */
  public static Ticker systemTicker() {
    return SYSTEM_TICKER;
  }

import static com.google.common.base.Preconditions.checkNotNull;

import java.io.FilterWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;

/** @author Colin Decker */
public class TestWriter extends FilterWriter {

  private final TestOutputStream out;

  public TestWriter(TestOption... options) throws IOException {

import java.io.FilterWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;

/**
 * A char sink for testing that has configurable behavior.
 *
 * @author Colin Decker
 */
public class TestCharSink extends CharSink implements TestStreamSupplier {

  private final TestByteSink byteSink;

  public TestCharSink(TestOption... options) {
    this.byteSink = new TestByteSink(options);

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");

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.EnumSet;

/**
 * Tests for the default implementations of {@code ByteSink} methods.
 *
 * @author Colin Decker
 */
public class ByteSinkTest extends IoTestCase {

  private final byte[] bytes = newPreFilledByteArray(10000);

  private TestByteSink sink;

  @Override
  protected void setUp() throws Exception {

        "The process cannot access the file because it is being used by another process.",
        "The process cannot access the file because another process has locked a portion of the file.",
        "The disk is full.",
        "A duplicate name exists on the network.",
        "The network name cannot be found.",
        "ERRnomoreconn.",
        "The file exists.",

import java.util.List;
import junit.framework.TestCase;

/**
 * @param <S> the source or sink type
 * @param <T> the data type (byte[] or String)
 * @param <F> the factory type
 * @author Colin Decker
 */
@AndroidIncompatible // TODO(b/230620681): Make this available (even though we won't run it).
public class SourceSinkTester<S, T, F extends SourceSinkFactory<S, T>> extends TestCase {

  static final String LOREM_IPSUM =

import static org.junit.Assert.assertThrows;

import java.io.IOException;
import java.nio.CharBuffer;
import junit.framework.TestCase;

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

  public void testReadEmptyString() throws IOException {
    assertReadsCorrectly("");
  }

             * return which would render the timeout effectively useless.
             */
            doConnect();
        } catch( Exception ex ) {
            ex0 = ex; // Defer to below where we're locked
            return;
        } finally {
            synchronized (run_thread) {
                if (run_thread != thread) {
                    /* Thread no longer the one setup for this transport --

  private static final int CRC32C_GENERATOR = 0x1EDC6F41; // 0x11EDC6F41
  private static final int CRC32C_GENERATOR_FLIPPED = Integer.reverse(CRC32C_GENERATOR);

  public void testCrc32cByteTable() {
    // See Hacker's Delight 2nd Edition, Figure 14-7.
    int[] expected = new int[256];
    for (int i = 0; i < expected.length; i++) {
      int crc = i;
      for (int j = 7; j >= 0; j--) {
        int mask = -(crc & 1);