Package org.apache.juneau.marshall.sse

Class SseSerializer

java.lang.Object

org.apache.juneau.marshall.Context

org.apache.juneau.marshall.MarshallingContextable

org.apache.juneau.marshall.MarshallingTraverseContext

org.apache.juneau.marshall.serializer.Serializer

org.apache.juneau.marshall.serializer.WriterSerializer

org.apache.juneau.marshall.sse.SseSerializer

All Implemented Interfaces:

Function<Object,String>, ThrowingFunction<Object,String>, RecordWritable

public class SseSerializer
extends WriterSerializer
implements RecordWritable

Serializes SseEvent objects to the text/event-stream wire format defined by the WHATWG Server-Sent Events spec.

Media types

Produces Content-Type types: text/event-stream.

Description

Accepts any of the following as input and emits one wire event per element followed by a blank line (the spec's "dispatch" boundary):

• A single SseEvent.
• Iterable<SseEvent>.
• An array SseEvent[].
• Stream<SseEvent>.

After each event is written, the session calls Writer.flush() so that downstream REST infrastructure flushes the underlying TCP socket and the event is delivered immediately to the client.

Notes:

• This class is thread safe and reusable.

See Also:

• SSE

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	SseSerializer.Builder	Builder class.

Nested classes/interfaces inherited from class org.apache.juneau.marshall.serializer.WriterSerializer

WriterSerializer.DefaultBuilder

Nested classes/interfaces inherited from class org.apache.juneau.marshall.serializer.Serializer

Serializer.Null

Field Summary

Fields

Modifier and Type	Field	Description
static final SseSerializer	DEFAULT	Default serializer, all default settings.
static final String	MEDIA_TYPE	Wire-format media type produced by this serializer: text/event-stream.

Fields inherited from class org.apache.juneau.marshall.serializer.WriterSerializer

maxIndent, quoteChar, quoteCharOverride, useWhitespace

Fields inherited from class org.apache.juneau.marshall.serializer.Serializer

accept, addBeanTypes, addRootType, keepNullProperties, listener, nonDefault, produces, sortCollections, sortMaps, trimEmptyCollections, trimEmptyMaps, trimStrings

Fields inherited from class org.apache.juneau.marshall.MarshallingContextable

marshallingContext

Fields inherited from class org.apache.juneau.marshall.Context

CONTEXT_APPLY_FILTER

Constructor Summary

Constructors

Constructor	Description
SseSerializer(SseSerializer.Builder builder)	Constructor.

Method Summary

Modifier and Type	Method	Description
SseSerializer.Builder	copy()	Creates a builder from this context object.
static SseSerializer.Builder	create()	Creates a new builder for this object.
SseSerializerSession.Builder	createSession()	Create a session builder based on the properties defined on this context.
SseSerializerSession	getSession()	Returns a session to use for this context.
boolean	isRecordStreaming()	Streaming-quality signal queryable before opening a cursor.
static void	writeComment(Writer w, String comment)	Writes a comment line (heartbeat) to the supplied writer in the SSE wire format and flushes it.
RecordWriter	writeRecords(Object output)	Convenience delegator that opens a RecordWriter over the output using default session arguments (mirrors WriterSerializer.write(Object)).

Methods inherited from class org.apache.juneau.marshall.serializer.WriterSerializer

applyThrows, getMaxIndent, getQuoteChar, getStreamCharset, isUseWhitespace, isWriterSerializer, println, properties, quoteChar, toString, write

Methods inherited from class org.apache.juneau.marshall.serializer.Serializer

createSerializerBuilder, doWrite, forEachAcceptMediaType, getListener, getMediaTypeRanges, getPrimaryMediaType, getResponseContentType, getResponseHeaders, getUriContext, getUriRelativity, getUriResolution, isAddBeanTypes, isAddRootType, isKeepNullProperties, isNonDefault, isSortCollections, isSortMaps, isTrimEmptyCollections, isTrimEmptyMaps, isTrimStrings, write, writeToString

Methods inherited from class org.apache.juneau.marshall.MarshallingTraverseContext

getDetectRecursions, getIgnoreRecursions, getInitialDepth, getMaxDepth, isDetectRecursions, isIgnoreRecursions, shouldDetectRecursions

Methods inherited from class org.apache.juneau.marshall.MarshallingContextable

getDurationFormat, getMarshallingContext, getPeriodFormat

Methods inherited from class org.apache.juneau.marshall.Context

createBuilder, getAnnotationProvider, init, isDebug, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.function.Function

andThen, compose

Methods inherited from interface org.apache.juneau.commons.function.ThrowingFunction

apply

Field Details

MEDIA_TYPE

public static final String MEDIA_TYPE

Wire-format media type produced by this serializer: text/event-stream.

See Also:

• Constant Field Values

DEFAULT

public static final SseSerializer DEFAULT

Default serializer, all default settings.

Constructor Details

SseSerializer

public SseSerializer(SseSerializer.Builder builder)

Constructor.

Parameters:

builder - The builder for this object.

Method Details

create

public static SseSerializer.Builder create()

Creates a new builder for this object.

Returns:

A new builder.

copy

public SseSerializer.Builder copy()

Description copied from class: Context

Creates a builder from this context object.

Builders are used to define new contexts (e.g. serializers, parsers) based on existing configurations.

Overrides:

copy in class WriterSerializer

Returns:

A new Builder object.

createSession

public SseSerializerSession.Builder createSession()

Description copied from class: Context

Create a session builder based on the properties defined on this context.

Use this method for creating sessions where you want to override basic settings. Otherwise, use Context.getSession() directly.

Overrides:

createSession in class WriterSerializer

Returns:

A new session builder.

getSession

public SseSerializerSession getSession()

Description copied from class: Context

Returns a session to use for this context.

Note that subclasses may opt to return a reusable non-modifiable session.

Overrides:

getSession in class WriterSerializer

Returns:

A new session object.

writeComment

public static void writeComment(Writer w,
 String comment)
                         throws IOException

Writes a comment line (heartbeat) to the supplied writer in the SSE wire format and flushes it.

Parameters:

w - The writer. Must not be null.

comment - The comment text. null is treated as an empty string.

Throws:

IOException - If a problem occurred writing to the underlying stream.

writeRecords

public RecordWriter writeRecords(Object output)
                          throws IOException

Convenience delegator that opens a RecordWriter over the output using default session arguments (mirrors WriterSerializer.write(Object)).

The real implementation lives on SseSerializerSession.writeRecords(Object). Callers that need request-derived configuration should call createSession() and invoke SseSerializerSession.writeRecords(Object) on the built session instead.

Specified by:

writeRecords in interface RecordWritable

Parameters:

output - The output.

Returns:

A new RecordWriter.

Throws:

IOException - If a problem occurred opening the underlying output.

isRecordStreaming

public boolean isRecordStreaming()

Description copied from interface: RecordWritable

Streaming-quality signal queryable before opening a cursor.

Specified by:

isRecordStreaming in interface RecordWritable

Returns:

true if RecordWritable.writeRecords(Object) returns an O(1)-memory streaming cursor; false for buffered (whole-value) formats backed by RecordAdapter.