// The comparator used by this map.  It's the same as that of sortedDelegate,
  // except that when sortedDelegate's comparator is null, it points to a
  // non-null instance of Ordering.natural().
  // (cpovirk: Is sortedDelegate's comparator really ever null?)
  // The comparator will likely also differ because of our nullAccepting hack.
  // See the bottom of the file for more information about it.

     * Do not instantiate.
     */
    protected PreparedStatementUtil() {
    }

    /**
     * Executes the query.
     *
     * @param ps
     *            {@link PreparedStatement}. Must not be {@literal null}.
     * @return {@link ResultSet}
     * @throws SQLRuntimeException
     *             If a {@link SQLException} occurs.
     */

 * @param context The context identifier for this request trace, helping to identify the scope or purpose
 *                of the request. May be null if no specific context is needed.
 * @param parent The parent request trace that led to this request, establishing the chain of nested
 *               operations. May be null for top-level requests.
 * @param data Additional data associated with this request trace, typically containing the actual request

   *
   * @param element the element to add one occurrence of; may be null only if explicitly allowed by
   *     the implementation
   * @return {@code true} always, since this call is required to modify the multiset, unlike other
   *     {@link Collection} types
   * @throws NullPointerException if {@code element} is null and this implementation does not permit
   *     null elements

    protected void finalize() throws Throwable {
        try {
            // Add null check to prevent NPE if object was not fully constructed
            if (this.usageCount != null && this.usageCount.get() != 0) {
                log.warn("Tree handle was not properly released, performing emergency cleanup: "
                        + (this.resourceLoc != null ? this.resourceLoc.getURL() : "unknown"));
                emergencyReleaseHandle();

    assertThrows(NullPointerException.class, () -> throwIfUnchecked(null));
  }

  @J2ktIncompatible
  @GwtIncompatible // propagateIfPossible
  // I guess it's technically a bug that ThrowIfUncheckedKnownUnchecked fires here.
  @SuppressWarnings("ThrowIfUncheckedKnownUnchecked")
  public void testPropageIfPossible_null() {
    propagateIfPossible(null);
  }

  @J2ktIncompatible

  }

  public void testToString() {
    assertEquals("foo=1", entry("foo", 1).toString());
  }

  public void testToStringNull() {
    assertEquals("null=1", entry(NK, 1).toString());
    assertEquals("foo=null", entry("foo", NV).toString());
    assertEquals("null=null", entry(NK, NV).toString());
  }

  public void testEquals() {
    Entry<String, Integer> foo1 = entry("foo", 1);

    assertThrows(NullPointerException.class, () -> table.put(null, 2, cellValue('d')));
    assertThrows(NullPointerException.class, () -> table.put("cat", null, cellValue('d')));
    if (supportsNullValues()) {
      assertNull(table.put("cat", 2, null));
      assertTrue(table.contains("cat", 2));
    } else {
      assertThrows(NullPointerException.class, () -> table.put("cat", 2, null));
    }
    assertSize(3);
  }

            URLStreamHandler handler = PROTOCOL_HANDLERS.get(protocol);
            if (handler != null) {
                return handler;
            }
            if (factory != null) {
                handler = factory.createURLStreamHandler(protocol);
            }
            if (handler == null) {
                final String path = System.getProperty(HANDLER_PKGS_PROPERTY);

 * @author higa
 * @param <E> the element type
 */
public class SLinkedList<E> implements Cloneable, Externalizable {

    static final long serialVersionUID = 1L;

    private transient Entry header = new Entry(null, null, null);

    private transient int size = 0;

    /**
     * Creates an {@link SLinkedList}.
     */
    public SLinkedList() {
        header.next = header;
        header.previous = header;
    }