String original = "Hello, World!";

        byte[] serialized = serializer.fromObjectToBinary(original);
        assertNotNull(serialized, "Serialized data should not be null");
        assertTrue("Serialized data should not be empty", serialized.length > 0);

        Object deserialized = serializer.fromBinaryToObject(serialized);
        assertNotNull(deserialized, "Deserialized object should not be null");

import com.esotericsoftware.kryo.serializers.CollectionSerializer;
import com.esotericsoftware.kryo.serializers.MapSerializer;

/**
 * A serializer class for handling object serialization and deserialization.
 * <p>
 * This class provides serialization capabilities using different serializers,
 * currently supporting Kryo and JavaBin serialization formats. The serializer

        return ObjectInputFilter.Status.REJECTED;
    };

    /**
     * Tests if the object can be serialized.
     *
     * @param obj the object to be serialized (must not be {@literal null})
     * @return the deserialized object
     */
    public static Object serialize(final Object obj) {
        assertArgumentNotNull("obj", obj);

        final byte[] binary = fromObjectToBinary(obj);

## Decision

We do not use Java serialization.
Instead, we use custom serialization where we explicitly describe how data objects should be serialized and deserialized.

For internal purposes, we use binary formats for their brevity.
We use the `Serializer` abstraction to separate the actual implementation of serialization from its uses.

When sharing data with external tools, we use JSON.

## Consequences

    For example, `data="hello"` produces `data: "hello"` on the wire (with
    quotes).
    """

    data: Annotated[
        Any,
        Doc(
            """
            The event payload.

            Can be any JSON-serializable value: a Pydantic model, dict, list,
            string, number, etc. It is **always** serialized to JSON: strings

   * concurrent maps whose content may change while the method is running.
   *
   * <p>The serialized output consists of the number of entries, first key, first value, second key,
   * second value, and so on.
   */
  static <K extends @Nullable Object, V extends @Nullable Object> void writeMap(
      Map<K, V> map, ObjectOutputStream stream) throws IOException {
    stream.writeInt(map.size());

  /*
   * The mainline copy of ImmutableMapValues doesn't produce this serialized form anymore, though
   * the backport does. For now, we're keeping the class declaration in *both* flavors so that both
   * flavors can read old data or data from the other flavor. However, we strongly discourage
   * relying on this, as we have made incompatible changes to serialized forms in the past and

It also gives you a lot of **responsibility**. You have to make sure that the data you return is correct, in the correct format, that it can be serialized, etc.

## Using the `jsonable_encoder` in a `Response` { #using-the-jsonable-encoder-in-a-response }

Because **FastAPI** doesn't make any changes to a `Response` you return, you have to make sure its contents are ready for it.

   * concurrent maps whose content may change while the method is running.
   *
   * <p>The serialized output consists of the number of entries, first key, first value, second key,
   * second value, and so on.
   */
  static <K extends @Nullable Object, V extends @Nullable Object> void writeMap(
      Map<K, V> map, ObjectOutputStream stream) throws IOException {
    stream.writeInt(map.size());

   * most once unless the underlying {@code get()} throws an exception. The supplier's serialized
   * form does not contain the cached value, which will be recalculated when {@code get()} is called
   * on the deserialized instance.
   *
   * <p>When the underlying delegate throws an exception then this memoizing supplier will keep