# Benutzerdefinierte Response – HTML, Stream, Datei, andere

Standardmäßig gibt **FastAPI** die Responses mittels `JSONResponse` zurück.

Sie können das überschreiben, indem Sie direkt eine `Response` zurückgeben, wie in [Eine Response direkt zurückgeben](response-directly.md){.internal-link target=_blank} gezeigt.

        verifyTokenKeep(() -> downloadpage(form.dictId));
        return kuromojiService.getKuromojiFile(form.dictId)
                .map(file -> asStream(new File(file.getPath()).getName()).contentTypeOctetStream().stream(out -> {
                    file.writeOut(out);
                }))
                .orElseGet(() -> {

import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.SortedSet;
import java.util.TreeSet;
import java.util.stream.Collector;
import org.jspecify.annotations.Nullable;

/**
 * GWT emulation of {@link com.google.common.collect.ImmutableSortedSet}.
 *
 * @author Hayward Chan
 */

            try {
                if (fileAttributeView instanceof final AclFileAttributeView aclFileAttributeView) {
                    aclFileAttributeView.getAcl().stream().forEach(acl -> {
                        final UserPrincipal principal = acl.principal();
                        if (logger.isDebugEnabled()) {

import com.google.common.testing.EqualsTester;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.Set;
import java.util.function.BiPredicate;
import java.util.stream.Collector;
import junit.framework.Test;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link ImmutableSet}.
 *

	magicUSTAR, versionUSTAR = "ustar\x00", "00"
	trailerSTAR              = "tar\x00"
)

// Size constants from various tar specifications.
const (
	blockSize  = 512 // Size of each block in a tar stream
	nameSize   = 100 // Max length of the name field in USTAR format
	prefixSize = 155 // Max length of the prefix field in USTAR format

	// Max length of a special file (PAX header, GNU long name or link).

            fail();
        } catch (final ChildUrlsException e) {
            final Set<RequestData> urlSet = e.getChildUrlList();
            assertEquals(5, urlSet.size());
            final List<String> urlList = urlSet.stream().map(x -> x.getUrl()).sorted().toList();
            assertEquals("ftp://localhost:10021/dir1", urlList.get(0));
            assertEquals("ftp://localhost:10021/dir2", urlList.get(1));

	case authTypeStreamingSigned, authTypeStreamingSignedTrailer:
		// Initialize stream signature verifier.
		rd, s3Err = newSignV4ChunkedReader(r, rAuthType == authTypeStreamingSignedTrailer)
		if s3Err != ErrNone {
			writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Err), r.URL)
			return
		}
	case authTypeStreamingUnsignedTrailer:
		// Initialize stream chunked reader with optional trailers.

        // Clean up metrics for connections that no longer exist
        connectionMetrics.entrySet().removeIf(entry -> {
            String key = entry.getKey();
            boolean exists = connections.stream().anyMatch(conn -> getConnectionKey(conn).equals(key));
            return !exists;
        });
    }

    /**
     * Get detailed health statistics
     */

	case authTypeStreamingSigned, authTypeStreamingSignedTrailer:
		// Initialize stream signature verifier.
		reader, s3Error = newSignV4ChunkedReader(r, rAuthType == authTypeStreamingSignedTrailer)
		if s3Error != ErrNone {
			writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
			return
		}
	case authTypeStreamingUnsignedTrailer:
		// Initialize stream signature verifier.