// any state.
	r := NewReader([]byte("0123456789"))
	var wg sync.WaitGroup
	for i := 0; i < 5; i++ {
		wg.Add(1)
		go func(i int) {
			defer wg.Done()
			var buf [1]byte
			r.ReadAt(buf[:], int64(i))
		}(i)
	}
	wg.Wait()
}

func TestEmptyReaderConcurrent(t *testing.T) {
	// Test for the race detector, to verify a Read that doesn't yield any bytes

	if n := len(eofR.buf); n != 0 {
		t.Fatalf("got %d bytes left in bufio.Reader source; want 0 bytes", n)
	}
	// To prove the point, check that there are still 5 bytes available to read.
	if n := r.Buffered(); n != 5 {
		t.Fatalf("got %d bytes buffered in bufio.Reader; want 5 bytes", n)
	}

	// This is the second read of 0 bytes.
	read, err = r.Read([]byte{})
	if err != nil {
		t.Fatalf("unexpected error: %v", err)

    List<byte[]> ordered =
        Arrays.asList(
            new byte[] {},
            new byte[] {LEAST},
            new byte[] {LEAST, LEAST},
            new byte[] {LEAST, (byte) 1},
            new byte[] {(byte) 1},
            new byte[] {(byte) 1, LEAST},
            new byte[] {GREATEST, GREATEST - (byte) 1},
            new byte[] {GREATEST, GREATEST},

    private static void verifyArcfourHMAC ( int usage, String expect, String key, byte[] bytes ) throws GeneralSecurityException {
        byte[] keybytes = Hex.decode(key);
        byte[] javaChecksum;
        if ( keybytes.length == 16 ) {
            javaChecksum = sun.security.krb5.internal.crypto.ArcFourHmac.calculateChecksum(keybytes, usage, bytes, 0, bytes.length);

        }
        else {

    DataInput in = new LittleEndianDataInputStream(new ByteArrayInputStream(data));
    byte[] b = new byte[data.length];
    in.readFully(b);
    assertEquals(Bytes.asList(data), Bytes.asList(b));
  }

  public void testReadUnsignedByte_eof() throws IOException {
    DataInput in = new LittleEndianDataInputStream(new ByteArrayInputStream(new byte[0]));
    assertThrows(EOFException.class, () -> in.readUnsignedByte());
  }

    DataInput in = new LittleEndianDataInputStream(new ByteArrayInputStream(data));
    byte[] b = new byte[data.length];
    in.readFully(b);
    assertEquals(Bytes.asList(data), Bytes.asList(b));
  }

  public void testReadUnsignedByte_eof() throws IOException {
    DataInput in = new LittleEndianDataInputStream(new ByteArrayInputStream(new byte[0]));
    assertThrows(EOFException.class, () -> in.readUnsignedByte());
  }

  /** Converts a string, which should contain only ascii-representable characters, to a byte[]. */
  static byte[] ascii(String string) {
    byte[] bytes = new byte[string.length()];
    for (int i = 0; i < string.length(); i++) {
      bytes[i] = (byte) string.charAt(i);
    }
    return bytes;
  }

  interface HashFn {
    byte[] hash(byte[] input, int seed);
  }

 * in which the key is truncated at 64 bytes (rather than being hashed
 * via MD5).
 */ 
public class HMACT64 extends MessageDigest implements Cloneable {

    private static final int BLOCK_LENGTH = 64;

    private static final byte IPAD = (byte) 0x36;

    private static final byte OPAD = (byte) 0x5c;

    private MessageDigest md5;

    private byte[] ipad = new byte[BLOCK_LENGTH];

 * in which the key is truncated at 64 bytes (rather than being hashed
 * via MD5).
 */
class HMACT64 extends MessageDigest implements Cloneable {

    private static final int BLOCK_LENGTH = 64;

    private static final byte IPAD = (byte) 0x36;

    private static final byte OPAD = (byte) 0x5c;

    private MessageDigest md5;

    private byte[] ipad = new byte[BLOCK_LENGTH];

		src      io.Reader
		skipLen  int64
		expected string
	}{
		{bytes.NewBuffer([]byte("")), 0, ""},
		{bytes.NewBuffer([]byte("")), 1, ""},
		{bytes.NewBuffer([]byte("abc")), 0, "abc"},
		{bytes.NewBuffer([]byte("abc")), 1, "bc"},
		{bytes.NewBuffer([]byte("abc")), 2, "c"},
		{bytes.NewBuffer([]byte("abc")), 3, ""},
		{bytes.NewBuffer([]byte("abc")), 4, ""},
	}
	for i, testCase := range testCases {