if (result == -1) {
      advance();
      return read(cbuf, off, len);
    }
    return result;
  }

  @Override
  public long skip(long n) throws IOException {
    Preconditions.checkArgument(n >= 0, "n is negative");
    if (n > 0) {
      while (current != null) {
        long result = current.skip(n);
        if (result > 0) {
          return result;
        }
        advance();
      }

    checkNotNull(rowKey);
    checkNotNull(columnKey);
    Integer rowIndex = rowKeyToIndex.get(rowKey);
    checkArgument(rowIndex != null, "Row %s not in %s", rowKey, rowList);
    Integer columnIndex = columnKeyToIndex.get(columnKey);
    checkArgument(columnIndex != null, "Column %s not in %s", columnKey, columnList);
    return set(rowIndex, columnIndex, value);
  }

  /*

package com.google.common.base;

import static com.google.common.base.Internal.toNanosSaturated;
import static com.google.common.base.NullnessCasts.uncheckedCastNullableTToT;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.util.concurrent.Futures.immediateCancelledFuture;
import static com.google.common.util.concurrent.Internal.toNanosSaturated;

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.primitives;

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

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Preconditions;

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.primitives;

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

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Preconditions;

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.collect.Maps.immutableEntry;
import static com.google.common.collect.testing.Helpers.mapEntry;
import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.math;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import static java.lang.Double.NaN;
import static java.lang.Double.doubleToLongBits;

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.collect.CollectPreconditions.checkNonnegative;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;

        State internalState, boolean shutdownWhenStartupFinishes, @Nullable Throwable failure) {
      checkArgument(
          !shutdownWhenStartupFinishes || internalState == STARTING,
          "shutdownWhenStartupFinishes can only be set if state is STARTING. Got %s instead.",
          internalState);
      checkArgument(
          (failure != null) == (internalState == FAILED),