* IllegalArgumentException} is thrown when the collection operation is performed. (This differs
   * from the {@code Collector} returned by {@link Collectors#toMap(Function, Function)}, which
   * throws an {@code IllegalStateException}.)
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K, V>
      Collector<T, ?, ImmutableSortedMap<K, V>> toImmutableSortedMap(
          Comparator<? super K> comparator,

   * {@code stream.map(function).collect(Collectors.toCollection(supplier))}.
   *
   * <p>To collect to an {@link ImmutableMultiset}, use {@link
   * ImmutableMultiset#toImmutableMultiset}.
   *
   * @since 22.0
   */
  public static <T extends @Nullable Object, E extends @Nullable Object, M extends Multiset<E>>
      Collector<T, ?, M> toMultiset(
          Function<? super T, E> elementFunction,

import java.util.NavigableMap;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link NavigableMap} whose contents will never change, with many other important properties

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.function.ToIntFunction;
import java.util.stream.Collector;
import javax.annotation.CheckForNull;

   * the collection operation is performed. (This differs from the {@code Collector} returned by
   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */

   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K extends Enum<K>, V>
      Collector<T, ?, ImmutableMap<K, V>> toImmutableEnumMap(

        ProblemCollector collector2 = ProblemCollectorFactory.newInstance(Collections.singletonList(problem));

        assertNotSame(collector1, collector2);
        assertEquals(0, collector1.getProblems().size());
        assertEquals(1, collector2.getProblems().size());
    }

        context.put("project.baseUri", "myBaseUri");
    }

    protected void assertProblemFree(SimpleProblemCollector collector) {
        assertEquals(0, collector.getErrors().size(), "Expected no errors");
        assertEquals(0, collector.getWarnings().size(), "Expected no warnings");
        assertEquals(0, collector.getFatals().size(), "Expected no fatals");
    }

    protected void assertCollectorState(

  public void testToImmutableBiMap() {
    Collector<Entry<String, Integer>, ?, ImmutableBiMap<String, Integer>> collector =
        toImmutableBiMap(Entry::getKey, Entry::getValue);
    Equivalence<ImmutableBiMap<String, Integer>> equivalence =
        Equivalence.equals()
            .<Entry<String, Integer>>pairwise()
            .onResultOf(ImmutableBiMap::entrySet);
    CollectorTester.of(collector, equivalence)
        .expectCollects(

        private final OutputStream stream;

        private final OutputStream collector;

        public CacheStream(OutputStream stream, OutputStream collector) {
            this.stream = stream;
            this.collector = collector;
        }

        public void close() throws IOException {
            stream.close();
            collector.close();
        }

        public void flush() throws IOException {