# モデル - より詳しく

先ほどの例に続き、複数の関連モデルを持つことが一般的です。

これはユーザーモデルの場合は特にそうです。なぜなら:

* **入力モデル** にはパスワードが必要です。
* **出力モデル**はパスワードをもつべきではありません。
* **データベースモデル**はおそらくハッシュ化されたパスワードが必要になるでしょう。

/// danger | "危険"

ユーザーの平文のパスワードは絶対に保存しないでください。常に認証に利用可能な「安全なハッシュ」を保存してください。

知らない方は、[セキュリティの章](security/simple-oauth2.md#password-hashing){.internal-link target=_blank}で「パスワードハッシュ」とは何かを学ぶことができます。

///

## 複数のモデル

## 🥙 🤝 ⏮️ ↔

🔜, 🔀 🤝 *➡ 🛠️* 📨 ↔ 📨.

👥 ⚙️ 🎏 `OAuth2PasswordRequestForm`. ⚫️ 🔌 🏠 `scopes` ⏮️ `list` `str`, ⏮️ 🔠 ↔ ⚫️ 📨 📨.

& 👥 📨 ↔ 🍕 🥙 🤝.

/// danger

🦁, 📥 👥 ❎ ↔ 📨 🔗 🤝.

✋️ 👆 🈸, 💂‍♂, 👆 🔜 ⚒ 💭 👆 🕴 🚮 ↔ 👈 👩‍💻 🤙 💪 ✔️, ⚖️ 🕐 👆 ✔️ 🔁.

///

```Python hl_lines="155"
{!../../docs_src/security/tutorial005.py!}
```

  @SuppressWarnings("nullness:initialization.field.uninitialized") // For J2KT (lateinit)
  @RetainedWith
  transient AbstractBiMap<V, K> inverse;

  /** Package-private constructor for creating a map-backed bimap. */
  AbstractBiMap(Map<K, V> forward, Map<V, K> backward) {
    setDelegates(forward, backward);
  }

  /** Private constructor for inverse bimap. */

                        .putAll(asList(entries))
                        .buildJdkBacked();
                  }
                })
            .named("ImmutableBiMap [JDK backed]")
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.SERIALIZABLE,
                CollectionFeature.KNOWN_ORDER,
                MapFeature.REJECTS_DUPLICATES_AT_CREATION,

We are still using the same `OAuth2PasswordRequestForm`. It includes a property `scopes` with a `list` of `str`, with each scope it received in the request.

And we return the scopes as part of the JWT token.

/// danger

For simplicity, here we are just adding the scopes received directly to the token.

//	specify a different capacity; it must be no smaller than the
//	length. For example, make([]int, 0, 10) allocates an underlying array
//	of size 10 and returns a slice of length 0 and capacity 10 that is
//	backed by this underlying array.
//	Map: An empty map is allocated with enough space to hold the
//	specified number of elements. The size may be omitted, in which case
//	a small starting size is allocated.

    for (int i = 0; i < len; i++) {
      // checkNotNull for GWT (do not optimize)
      array[i] = (Boolean) checkNotNull(boxedArray[i]);
    }
    return array;
  }

  /**
   * Returns a fixed-size list backed by the specified array, similar to {@link
   * Arrays#asList(Object[])}. The list supports {@link List#set(int, Object)}, but any attempt to
   * set a value to {@code null} will result in a {@link NullPointerException}.
   *

import java.util.Set;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link BiMap} backed by two hash tables. This implementation allows null keys and values. A
 * {@code HashBiMap} and its inverse are both serializable.
 *
 * <p>This implementation guarantees insertion-based iteration order of its keys.
 *

    for (int i = 0; i < len; i++) {
      // checkNotNull for GWT (do not optimize)
      array[i] = (Boolean) checkNotNull(boxedArray[i]);
    }
    return array;
  }

  /**
   * Returns a fixed-size list backed by the specified array, similar to {@link
   * Arrays#asList(Object[])}. The list supports {@link List#set(int, Object)}, but any attempt to
   * set a value to {@code null} will result in a {@link NullPointerException}.
   *

    }

    /**
     * Returns a new immutable array. The builder can continue to be used after this call, to append
     * more values and build again.
     *
     * <p><b>Performance note:</b> the returned array is backed by the same array as the builder, so
     * no data is copied as part of this step, but this may occupy more memory than strictly
     * necessary. To copy the data to a right-sized backing array, use {@code .build().trimmed()}.