* @param root the Maven Dependency, must not be {@code null}
     * @param scope the {link PathScope} to collect dependencies, must not be {@code null}
     * @return the collection result, never {@code null}
     * @throws DependencyResolverException if the dependency tree could not be built
     * @throws IllegalArgumentException if an argument is null or invalid

      Set<Object> keys = cache.asMap().keySet();
      assertThat(keys.remove(null)).isFalse();
      assertThat(keys.remove(6)).isFalse();
      assertThat(keys.remove(-6)).isFalse();
      assertThat(keys.removeAll(asList(null, 0, 15, 1500))).isFalse();
      assertThat(keys.retainAll(asList(null, 0, 15, 1500))).isFalse();
      checkEmpty(keys);
      checkEmpty(cache);
    }
  }

      int size = (keyList == null) ? 0 : keyList.count;
      checkPositionIndex(index, size);
      if (index >= (size / 2)) {
        previous = (keyList == null) ? null : keyList.tail;
        nextIndex = size;
        while (index++ < size) {
          previous();
        }
      } else {
        next = (keyList == null) ? null : keyList.head;
        while (index-- > 0) {
          next();

            "keyword", 0, 0, null, null, false, null, null, null, null, null, false);
    protected final ColumnInfo _columnSearchWord = cci("searchWord", "searchWord", null, null, String.class, "searchWord", null, false,
            false, false, "keyword", 0, 0, null, null, false, null, null, null, null, null, false);

        // Test equals with null input - should not throw, uses null-safe comparison
        StopwordsItem item1 = new StopwordsItem(1, null);
        StopwordsItem item2 = new StopwordsItem(2, null);
        StopwordsItem item3 = new StopwordsItem(1, "word");

        // Two items with null input should be equal
        assertTrue(item1.equals(item2));

        // Item with null input should not equal item with non-null input

        DefaultProblemCollector collector = new DefaultProblemCollector(null);

        collector.add(null, "PROBLEM1", -1, -1, null);

        collector.setSource("SOURCE_PROBLEM2");
        collector.add(null, "PROBLEM2", -1, -1, null);

        collector.setSource("SOURCE_PROBLEM3");
        collector.add(null, "PROBLEM3", -1, -1, null);

        assertEquals("", collector.getProblems().get(0).getSource());

        if (methodDescs == null) {
            return null;
        }
        for (final MethodDesc methodDesc : methodDescs) {
            if (Arrays.equals(paramTypes, methodDesc.getParameterTypes())) {
                return methodDesc;
            }
        }
        return null;
    }

    @Override

     * Returns a defensive copy to prevent external modification.
     *
     * @return array of new input sequences (defensive copy), or null if no updates are pending
     */
    public String[] getNewInputs() {
        return newInputs == null ? null : newInputs.clone();
    }

    /**
     * Sets the array of new input character sequences for update operations.
     *

    protected final ColumnInfo _columnSortOrder = cci("sortOrder", "sortOrder", null, null, Integer.class, "sortOrder", null, false, false,
            false, "Integer", 0, 0, null, null, false, null, null, null, null, null, false);
    protected final ColumnInfo _columnTarget = cci("target", "target", null, null, String.class, "target", null, false, false, false,

    void equalsAndHashCode_subjectSemantics() {
        Kerb5Authenticator a = new Kerb5Authenticator((Subject) null);
        Kerb5Authenticator b = new Kerb5Authenticator((Subject) null);

        // Both null subjects -> equal
        assertEquals(a, b);
        assertEquals(a.hashCode(), b.hashCode());

        // Mixed null/non-null -> not equal
        Kerb5Authenticator c = new Kerb5Authenticator(new Subject());