# Bigger Applications - Multiple Files { #bigger-applications-multiple-files }

If you are building an application or a web API, it's rarely the case that you can put everything in a single file.

**FastAPI** provides a convenience tool to structure your application while keeping all the flexibility.

/// info

If you come from Flask, this would be the equivalent of Flask's Blueprints.

///

## An example file structure { #an-example-file-structure }

        "java.math.*",
        "org.codelibs.*",
        "[*" // Allow arrays
    );

    /**
     * Default ObjectInputFilter that only allows safe classes to be deserialized.
     * This filter rejects potentially dangerous classes while allowing common safe types.
     */
    private static final ObjectInputFilter DEFAULT_FILTER = filterInfo -> {
        final Class<?> serialClass = filterInfo.serialClass();

  }

  @Override
  public ElementOrder<N> incidentEdgeOrder() {
    return ElementOrder.stable();
  }

  @Override
  public ImmutableGraph<N> asGraph() {
    return new ImmutableGraph<>(this); // safe because the view is effectively immutable
  }

  private static <N, V> ImmutableMap<N, GraphConnections<N, V>> getNodeConnections(
      ValueGraph<N, V> graph) {

- Names inside ZIP files are kept unmodified, but some may lead to invalid paths. See [Object key naming guidelines](https://docs.aws.amazon.com/AmazonS3/latest/userguide/object-keys.html) on safe names.
- This API behavior is limited for following **read** operations on files inside a zip archive:
  - `HeadObject`
  - `GetObject`
  - `ListObjectsV2`

 * invoke methods, they invoke methods on the {@code ForwardingQueue}.
 *
 * <p>The {@code standard} methods are not guaranteed to be thread-safe, even when all of the
 * methods that they depend on are thread-safe.
 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible

	"compress/flate"
	"errors"
	"io"
	"sync"
)

// A Compressor returns a new compressing writer, writing to w.
// The WriteCloser's Close method must be used to flush pending data to w.
// The Compressor itself must be safe to invoke from multiple goroutines
// simultaneously, but each returned writer will be used only by
// one goroutine at a time.
type Compressor func(w io.Writer) (io.WriteCloser, error)

     * (never less than 1, never more than 2), depending on project packaging.
     * <p>
     * The list's first element is ALWAYS the project POM artifact. Presence of second element in the list depends
     * solely on the project packaging.
     *
     * @see #getPackaging()
     * @see #getPomArtifact()
     * @see #getMainArtifact()
     * @see org.apache.maven.api.services.ArtifactManager#getPath(Artifact)
     */

      implied, including, without limitation, any warranties or conditions
      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
      PARTICULAR PURPOSE. You are solely responsible for determining the
      appropriateness of using or redistributing the Work and assume any
      risks associated with Your exercise of permissions under this License.

      implied, including, without limitation, any warranties or conditions
      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
      PARTICULAR PURPOSE. You are solely responsible for determining the
      appropriateness of using or redistributing the Work and assume any
      risks associated with Your exercise of permissions under this License.

      bufferSize = 1;
    } else if (bufferSize < k) {
      buffer[bufferSize++] = elem;
      // uncheckedCastNullableTToT is safe because bufferSize > 0.
      if (comparator.compare(elem, uncheckedCastNullableTToT(threshold)) > 0) {
        threshold = elem;
      }
      // uncheckedCastNullableTToT is safe because bufferSize > 0.
    } else if (comparator.compare(elem, uncheckedCastNullableTToT(threshold)) < 0) {