# Server-Sent Events (SSE) { #server-sent-events-sse }

**Server-Sent Events** (SSE) を使うと、クライアントへデータをストリーミングできます。

これは[JSON Lines のストリーミング](stream-json-lines.md)に似ていますが、`text/event-stream` フォーマットを使用します。これはブラウザがネイティブに [`EventSource` API](https://developer.mozilla.org/en-US/docs/Web/API/EventSource) でサポートしています。

/// info | 情報

FastAPI 0.135.0 で追加されました。

///

## Server-Sent Events とは { #what-are-server-sent-events }

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import static java.util.function.Function.identity;
import static java.util.stream.Collectors.toMap;

/**
 * DefaultLifecycleMapping
 */
public class DefaultLifecycleMapping implements LifecycleMapping {

    private List<Lifecycle> lifecycles;

        final PermissionHelper permissionHelper = ComponentUtil.getPermissionHelper();
        return split(permissionsText, "\n")
                .get(stream -> stream.map(permissionHelper::encode).filter(StringUtil::isNotBlank).distinct().toArray(String[]::new));
    }

    // ===================================================================================

            // Analyze timing consistency across threads
            if (!timings.isEmpty()) {
                double avgTime = timings.stream().mapToLong(Long::longValue).average().orElse(0.0);
                long maxTime = timings.stream().mapToLong(Long::longValue).max().orElse(0L);
                long minTime = timings.stream().mapToLong(Long::longValue).min().orElse(0L);

                double variance = (maxTime - minTime) / avgTime;

   * @serialData the ConcurrentMap of elements and their counts.
   */
    private void writeObject(ObjectOutputStream stream) throws IOException {
    stream.defaultWriteObject();
    stream.writeObject(countMap);
  }

    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    @SuppressWarnings("unchecked") // reading data stored by writeObject

     *
     * @return The created OpenSearch client.
     */
    protected Client createClient() {
        final String[] hosts =
                split(address, ",").get(stream -> stream.map(String::trim).filter(StringUtil::isNotEmpty).toArray(n -> new String[n]));
        final Settings settings = Settings.builder().putList("http.hosts", hosts).build();
        return new HttpClient(settings, null);
    }

     */
    public String getSimpleName() {
        return new File(path).getName();
    }

    /**
     * Updates the dictionary file with the given input stream.
     *
     * @param in The input stream.
     * @throws IOException If an I/O error occurs.
     */
    public synchronized void update(final InputStream in) throws IOException {

   */
  private CharBuffer charBuffer;

  /**
   * byteBuffer holds encoded characters that have not yet been sent to the caller of the input
   * stream. When encoding it is "unflipped" (encoded bytes between 0 and position) and when
   * draining it is flipped (undrained bytes between position and limit).
   */
  private ByteBuffer byteBuffer;

import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.Properties;
import java.util.stream.Stream;

import org.apache.maven.RepositoryUtils;
import org.apache.maven.api.Language;
import org.apache.maven.api.ProducedArtifact;
import org.apache.maven.api.Project;
import org.apache.maven.api.ProjectScope;

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