## Optimize Response Performance - Response Model - Return Type { #optimize-response-performance-response-model-return-type }

   * next} field is lazily initialized. The type of that field would be {@code @Nullable T}, and the
   * code would be responsible for populating a "real" {@code T} (which might still be the value
   * {@code null}!) before returning it to callers. Depending on how the code is structured, a
   * nullness analysis might not understand that the field has been populated. To avoid that problem

 * implementations to decide which objects to process and how to optimize them.</p>
 *
 * @since 4.0.0
 */
public interface ModelObjectProcessor {

    /**
     * Process a model object, potentially returning a pooled or optimized version.
     *
     * <p>This method is called during model building for various model objects.
     * Implementations can:</p>
     * <ul>

import (
	"bufio"
	"bytes"
	"encoding/binary"
	"flag"
	"fmt"
	"hash/crc32"
	"log"
	"os"
	"strings"

	"github.com/dchest/siphash"
	"github.com/google/uuid"
)

// hashes the key returning an integer based on the input algorithm.
// This function currently supports
// - SIPMOD
func sipHashMod(key string, cardinality int, id [16]byte) int {
	if cardinality <= 0 {
		return -1
	}

/// tip

Now we use `response_model=HeroPublic` instead of the **return type annotation** `-> HeroPublic` because the value that we are returning is actually *not* a `HeroPublic`.

If we had declared `-> HeroPublic`, your editor and linter would complain (rightfully so) that you are returning a `Hero` instead of a `HeroPublic`.

 * which has a method {@code getParents()} that retrieves its predecessors in a graph:
 *
 * {@snippet :
 * someGraphAlgorithm(startNode, MyNode::getParents);
 * }
 *
 * <p>If you have some other mechanism for returning the predecessors of a node, or one that doesn't
 * return a {@code Iterable<? extends N>}, then you can use a lambda to perform a more general
 * transformation:
 *
 * {@snippet :

            int | None,
            Doc(
                """
                The default status code to be used for the response.

                You could override the status code by returning a response directly.

                Read more about it in the
                [FastAPI docs for Response Status Code](https://fastapi.tiangolo.com/tutorial/response-status-code/).
                """

   */

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testRemoveAll_nullCollectionReferenceEmptySubject() {
    try {
      collection.removeAll(null);
      // Returning successfully is not ideal, but tolerated.
    } catch (NullPointerException tolerated) {
    }
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)

   */

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testRemoveAll_nullCollectionReferenceEmptySubject() {
    try {
      collection.removeAll(null);
      // Returning successfully is not ideal, but tolerated.
    } catch (NullPointerException tolerated) {
    }
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)

 * which has a method {@code getChildren()} that retrieves its successors in a graph:
 *
 * {@snippet :
 * someGraphAlgorithm(startNode, MyNode::getChildren);
 * }
 *
 * <p>If you have some other mechanism for returning the successors of a node, or one that doesn't
 * return an {@code Iterable<? extends N>}, then you can use a lambda to perform a more general
 * transformation:
 *
 * {@snippet :