* from lower versions plus additional checks specific to that version.
     */
    enum Version {
        /**
         * Base validation level that applies to all POM versions.
         * Includes fundamental structural validations.
         */
        BASE,

        /**
         * Validation for Maven 2.0 POM format.
         */
        V20,

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

package com.google.common.annotations;

/**
 * Annotates a program element that exists, or is more widely visible than otherwise necessary, only
 * for use in test code.
 *
 * <p><b>Do not use this interface</b> for public or protected declarations: it is a fig leaf for

  }

  protected abstract Collection<String> create(String[] elements);

  @Override
  public String[] createArray(int length) {
    return new String[length];
  }

  /** Returns the original element list, unchanged. */
  @Override
  public List<String> order(List<String> insertionOrder) {
    return insertionOrder;
  }

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * The annotated element must not be null.
 * <p>
 * Annotated fields must not be null after construction has completed.
 * <p>
 * When this annotation is applied to a method it applies to the method return value.
 *
 * @see Nullable

  public void testPutAllNullForbidden() {
    assertThrows(NullPointerException.class, () -> multimap().putAll(null, singletonList(v3())));
  }

  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAllEmptyCollectionOnAbsentKey() {
    assertFalse(multimap().putAll(k3(), Collections.emptyList()));
    expectUnchanged();
  }

        if (!preserveModelVersion) {
            /*
             * If the <build> contains <source> elements, it is not compatible with the Maven 4.0.0 model.
             * Remove the full <build> element instead of removing only the <sources> element, because the
             * build without sources does not mean much. Reminder: this removal can be disabled by setting

  }

  @Override
  public void testNulls() throws Exception {
    try {
      super.testNulls();
    } catch (AssertionError e) {
      assertWithMessage("Method did not throw null pointer OR element not in graph exception.")
          .that(e)
          .hasCauseThat()
          .hasMessageThat()
          .contains(ERROR_ELEMENT_NOT_IN_GRAPH);
    }
  }

              public Collection<@Nullable String> create(@Nullable String[] elements) {
                List<@Nullable String> list = new ArrayList<>();
                for (String element : elements) {
                  list.add((element == null) ? null : "q" + element);
                }
                return Collections2.transform(
                    list, from -> isNullOrEmpty(from) ? null : from.substring(1));
              }

     */
    protected void createFilterChain() {
        FilterChain chain = createDefaultFilterChain();
        for (final Filter element : filterList) {
            chain = appendFilterChain(element, chain);
        }
        filterChain = chain;
    }

    /**
     * Appends a filter to the existing filter chain.
     *
     * @param filter the filter to append

  @CollectionSize.Require(absent = ZERO)
  public void testRemove_present() {
    getSet().remove(e0());
    assertFalse(
        "After remove(present) a set should not contain the removed element.",
        getSet().contains(e0()));
  }