*
     * @return The problems that caused this exception, never {@code null}.
     */
    public List<ModelProblem> getProblems() {
        if (result == null) {
            return Collections.emptyList();
        }
        return Collections.unmodifiableList(result.getProblems());
    }

    private static String toMessage(ModelBuildingResult result) {
        if (result != null && !result.getModelIds().isEmpty()) {

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.execution;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.Predicate;

import static java.util.stream.Collectors.toSet;

/**

import static com.google.common.collect.CollectPreconditions.checkNonnegative;
import static java.util.Arrays.asList;
import static java.util.Arrays.sort;
import static java.util.Collections.emptyList;
import static java.util.Collections.sort;
import static java.util.Collections.unmodifiableList;

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

import static com.google.common.collect.testing.IteratorFeature.MODIFIABLE;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static java.util.Collections.emptyList;
import static java.util.Collections.singletonList;
import static java.util.Collections.unmodifiableList;

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

import static com.google.common.graph.GraphConstants.INNER_LOAD_FACTOR;

import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterators;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**

    // the behaviour of the non-GWT implementation of newConcurrentHashSet().
    // On the other hand HashSet might be better for code size if apps aren't
    // already using Collections.newSetFromMap and ConcurrentHashMap.
    return Collections.newSetFromMap(new ConcurrentHashMap<E, Boolean>());
  }

  static <E extends @Nullable Object> Set<E> newLinkedHashSetWithExpectedSize(int expectedSize) {

/**
 * Construct a version range from a specification.
 *
 */
public class VersionRange {
    private static final Map<String, VersionRange> CACHE_SPEC = Collections.synchronizedMap(new WeakHashMap<>());

    private static final Map<String, VersionRange> CACHE_VERSION = Collections.synchronizedMap(new WeakHashMap<>());

    private final ArtifactVersion recommendedVersion;

    private final List<Restriction> restrictions;

import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.testers.NavigableSetNavigationTester;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.NavigableSet;
import java.util.Set;
import java.util.SortedSet;
import junit.framework.TestSuite;

/**

import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.NavigableSet;
import java.util.Set;
import java.util.SortedSet;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.mockito.Mockito.doNothing;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.when;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import javax.security.auth.Subject;
import javax.security.auth.kerberos.KerberosKey;
import javax.security.auth.login.LoginContext;