import static com.google.common.collect.Tables.newCustomTable;
import static com.google.common.truth.Truth.assertThat;

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Supplier;
import java.util.Map;
import java.util.TreeMap;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Test cases for {@link Tables#newCustomTable}.
 *
 * @author Jared Levy
 */
@GwtCompatible

   *     for a given row key
   * @throws IllegalArgumentException if {@code backingMap} is not empty
   * @since 10.0
   */
  public static <R, C, V> Table<R, C, V> newCustomTable(
      Map<R, Map<C, V>> backingMap, Supplier<? extends Map<C, V>> factory) {
    checkArgument(backingMap.isEmpty());
    checkNotNull(factory);