try {
      return parseUnsignedInt(request.rawValue, request.radix);
    } catch (NumberFormatException e) {
      NumberFormatException decodeException =
          new NumberFormatException("Error parsing value: " + stringValue);
      decodeException.initCause(e);
      throw decodeException;
    }
  }

  /**
   * Returns the unsigned {@code int} value represented by the given decimal string.
   *

    try {
      return parseUnsignedInt(request.rawValue, request.radix);
    } catch (NumberFormatException e) {
      NumberFormatException decodeException =
          new NumberFormatException("Error parsing value: " + stringValue);
      decodeException.initCause(e);
      throw decodeException;
    }
  }

  /**
   * Returns the unsigned {@code int} value represented by the given decimal string.
   *

 *     class (such as {@link #named(String)}) return this type, so that Builder methods of more
 *     derived classes can be chained onto them without casting.
 * @param <G> The type of the generator to be passed to testers in the generated test suite. An
 *     instance of G should somehow provide an instance of the class under test, plus any other

 * Tests that all package-private {@code writeReplace} methods are overridden in any existing
 * subclasses. Without such overrides, optimizers might put a {@code writeReplace}-containing class
 * and its subclass in different packages, causing the serialization system to fail to invoke {@code
 * writeReplace} when serializing an instance of the subclass. For an example of this problem, see
 * b/310253115.
 */
public class WriteReplaceOverridesTest extends TestCase {

import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.hash.Hashing;
import com.google.common.primitives.UnsignedBytes;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;

      Method method = null;
      try {
        method = annotationClass.getMethod(propertyName);
      } catch (NoSuchMethodException e) {
        throw new AssertionError("Annotation is missing required method", e);
      }
      final Class<?> returnType = method.getReturnType();
      assertTrue(
          rootLocaleFormat("%s.%s() must return an array.", annotationClass, propertyName),

书接上文，多个关联模型这种情况很常见。

特别是用户模型，因为：

* **输入模型**应该含密码
* **输出模型**不应含密码
* **数据库模型**需要加密的密码

/// danger | "危险"

千万不要存储用户的明文密码。始终存储可以进行验证的**安全哈希值**。

如果不了解这方面的知识，请参阅[安全性中的章节](security/simple-oauth2.md#password-hashing){.internal-link target=_blank}，了解什么是**密码哈希**。

///

## 多个模型

下面的代码展示了不同模型处理密码字段的方式，及使用位置的大致思路：

//// tab | Python 3.10+

```Python hl_lines="7  9  14  20  22  27-28  31-33  38-39"

* <abbr title="also known as: serialization, parsing, marshalling">Conversion</abbr> of input data: coming from the network to Python data and types. Reading from:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Forms.
    * Files.

Mas com todos os benefícios:

* Suporte do editor (compleção em todo canto!)
* Conversão de dados (leia-se parsing/serialização)
* Validação de dados
* Documentação dos esquemas

	if b[0] == '{' && b[len(b)-1] == '}' { // JSON object
		var c ciphertext
		if err := c.UnmarshalJSON(b); err != nil {
			// It may happen that a random ciphertext starts with '{' and ends with '}'.
			// In such a case, parsing will fail but we must not return an error. Instead
			// we return the ciphertext as it is.
			return b, kms.AES256
		}

		b = b[:0]
		b = append(b, c.Bytes...)
		b = append(b, c.IV...)