* @param parent The parent model, may be <code>null</code>.
     * @param childDirectory The directory defined in child model, may be <code>null</code>.
     * @return The path adjustment, can be empty but never <code>null</code>.
     */
    private String getChildPathAdjustment(Model child, Model parent, String childDirectory) {
        String adjustment = "";

        if (parent != null) {

* The **input model** needs to be able to have a password.
* The **output model** should not have a password.
* The **database model** would probably need to have a hashed password.

/// danger

Never store user's plaintext passwords. Always store a "secure hash" that you can then verify.

    private final int size;

    ImmutableArrayMap(int size) {
      this.size = size;
    }

    abstract ImmutableMap<K, Integer> keyToIndex();

    // True if getValue never returns null.
    private boolean isFull() {
      return size == keyToIndex().size();
    }

    K getKey(int index) {
      return keyToIndex().keySet().asList().get(index);
    }

          Function<? super T, ? extends V> valueFunction) {
    return CollectCollectors.toImmutableBiMap(keyFunction, valueFunction);
  }

  // Casting to any type is safe because the set will never hold any elements.
  @SuppressWarnings("unchecked")
  public static <K, V> ImmutableBiMap<K, V> of() {
    return (ImmutableBiMap<K, V>) RegularImmutableBiMap.EMPTY;
  }

   * Returns a map of the values associated with {@code keys}, creating or retrieving those values
   * if necessary. The returned map contains entries that were already cached, combined with newly
   * loaded entries; it will never contain null keys or values.
   *
   * <p>Caches loaded by a {@link CacheLoader} will issue a single request to {@link
   * CacheLoader#loadAll} for all keys which are not already present in the cache. All entries

    assertThat(certificate.getSubjectX500Principal().name)
      .isEqualTo("CN=cash.app,OU=engineering")
  }

  @Test
  fun decodeRsa512() {
    // The certificate + private key below was generated with OpenSSL. Never generate certificates
    // with MD5 or 512-bit RSA; that's insecure!
    //
    // openssl req \
    //   -x509 \
    //   -md5 \
    //   -nodes \
    //   -days 1 \
    //   -newkey rsa:512 \

// (i.e. enclosed in parentheses like `IN (1,2,4)`) or it could be a JSON path
// expression (as in `8.5 IN s.nested[*][*]`). Specifically, it cannot be an
// `Expression` as an expression can never evaluate to a list.
type In struct {
	JPathExpr *JSONPath `parser:"@@"`
	ListExpr  *ListExpr `parser:"| @@"`
}

// Grammar for Operand:
//
// operand → multOp ( ("-" | "+") multOp )*

Note that when adding a lazy property to an existing class, you need to check if instances of the class are instantiated via ObjectFactory. Most classes are instantiated this way, but it's possible that a class without any lazy properties was never updated to use it. A tell-tale sign that an object is not instantiated via the ObjectFactory are direct calls to the constructor with new.

### Existing properties in existing classes

      case CEILING:
      case UP:
        return logFloor + lessThanBranchFree(floorPow, x);
      case HALF_DOWN:
      case HALF_UP:
      case HALF_EVEN:
        // sqrt(10) is irrational, so log10(x)-logFloor is never exactly 0.5
        return logFloor + lessThanBranchFree(halfPowersOf10[logFloor], x);
    }
    throw new AssertionError();
  }

  @GwtIncompatible // TODO
  static int log10Floor(long x) {
    /*

import com.google.errorprone.annotations.Immutable;
import com.google.errorprone.annotations.InlineMe;

/**
 * A {@link ValueGraph} whose elements and structural relationships will never change. Instances of
 * this class may be obtained with {@link #copyOf(ValueGraph)}.
 *
 * <p>See the Guava User's Guide's <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#immutable-implementations">discussion