* @throws IOException if an I/O error occurs
   */
  @CanIgnoreReturnValue // to skip a line
  public @Nullable String readLine() throws IOException {
    while (lines.peek() == null) {
      Java8Compatibility.clear(cbuf);
      // The default implementation of Reader#read(CharBuffer) allocates a
      // temporary char[], so we call Reader#read(char[], int, int) instead.

    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(ByteBuffer b) {
    if (b.hasArray()) {
      putBytes(b.array(), b.arrayOffset() + b.position(), b.remaining());
      Java8Compatibility.position(b, b.limit());
    } else {
      for (int remaining = b.remaining(); remaining > 0; remaining--) {
        putByte(b.get());
      }
    }
    return this;
  }

  @Override

        int limit = pos + random.nextInt(value.length - pos + 1);
        for (PrimitiveSink sink : sinks) {
          ByteBuffer buffer = ByteBuffer.wrap(value);
          Java8Compatibility.position(buffer, pos);
          Java8Compatibility.limit(buffer, limit);
          sink.putBytes(buffer);
          assertEquals(limit, buffer.limit());
          assertEquals(limit, buffer.position());
        }
      }
    },

        }
        return this;
      }

      @Override
      public Hasher putBytes(ByteBuffer bytes) {
        int pos = bytes.position();
        for (Hasher hasher : hashers) {
          Java8Compatibility.position(bytes, pos);
          hasher.putBytes(bytes);
        }
        return this;
      }

      @Override
      public Hasher putShort(short s) {
        for (Hasher hasher : hashers) {

      ByteBuffer newBuffer = ByteBuffer.allocate(newCapacity).order(ByteOrder.LITTLE_ENDIAN);

      // We must switch the old buffer to read mode to extract data
      Java8Compatibility.flip(buffer);

      newBuffer.put(buffer);

      // Swap references, newBuffer is already in write mode at the correct position
      this.buffer = newBuffer;
    }

    @Override

      StringBuilder builder = new StringBuilder();
      CharBuffer buffer = CharBuffer.allocate(100);
      while (reader.read(buffer) != -1) {
        Java8Compatibility.flip(buffer);
        builder.append(buffer);
        Java8Compatibility.clear(buffer);
      }
      return builder.toString();
    }
  }

  private static class UrlByteSourceFactory extends FileByteSourceFactory {

        int limit = pos + random.nextInt(value.length - pos + 1);
        for (PrimitiveSink sink : sinks) {
          ByteBuffer buffer = ByteBuffer.wrap(value);
          Java8Compatibility.position(buffer, pos);
          Java8Compatibility.limit(buffer, limit);
          sink.putBytes(buffer);
          assertEquals(limit, buffer.limit());
          assertEquals(limit, buffer.position());
        }
      }
    },

    }

    ByteBuffer buf = ByteBuffer.wrap(createBuffer());
    long total = 0;
    while (from.read(buf) != -1) {
      Java8Compatibility.flip(buf);
      while (buf.hasRemaining()) {
        total += to.write(buf);
      }
      Java8Compatibility.clear(buf);
    }
    return total;
  }

  /** Max array length on JVM. */
  private static final int MAX_ARRAY_LEN = Integer.MAX_VALUE - 8;