OutboundEvent.java
/*
* Copyright (c) 2012, 2019 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.jersey.media.sse;
import java.lang.reflect.Type;
import javax.ws.rs.core.GenericEntity;
import javax.ws.rs.core.GenericType;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.sse.OutboundSseEvent;
import org.glassfish.jersey.internal.util.ReflectionHelper;
/**
* Representation of a single outbound SSE event.
*
* @author Pavel Bucek
* @author Marek Potociar
*/
public final class OutboundEvent implements OutboundSseEvent {
private final String name;
private final String comment;
private final String id;
private final GenericType type;
private final MediaType mediaType;
private final Object data;
private final long reconnectDelay;
/**
* Used for creating {@link OutboundEvent} instances.
*/
public static class Builder implements OutboundSseEvent.Builder {
private String name;
private String comment;
private String id;
private long reconnectDelay = SseFeature.RECONNECT_NOT_SET;
private GenericType type;
private Object data;
private MediaType mediaType = MediaType.TEXT_PLAIN_TYPE;
/**
* Set event name.
*
* <p>
* Will be send as a value of the SSE {@code "event"} field. This field is optional.
* </p>
*
* @param name event name.
* @return updated builder instance.
*/
public Builder name(String name) {
this.name = name;
return this;
}
/**
* Set event id.
* <p>
* Will be send as a value of the SSE {@code "id"} field. This field is optional.
* </p>
*
* @param id event id.
* @return updated builder instance.
*/
public Builder id(String id) {
this.id = id;
return this;
}
/**
* Set reconnection delay (in milliseconds) that indicates how long the event receiver should wait
* before attempting to reconnect in case a connection to SSE event source is lost.
* <p>
* Will be send as a value of the SSE {@code "retry"} field. This field is optional.
* </p>
* <p>
* Absence of a value of this field in an {@link OutboundEvent} instance
* is indicated by {@link SseFeature#RECONNECT_NOT_SET} value returned from
* {@link org.glassfish.jersey.media.sse.OutboundEvent#getReconnectDelay()}.
* </p>
*
* @param milliseconds reconnection delay in milliseconds. Negative values un-set the reconnection delay.
* @return updated builder instance.
* @since 2.3
*/
public Builder reconnectDelay(long milliseconds) {
if (milliseconds < 0) {
milliseconds = SseFeature.RECONNECT_NOT_SET;
}
this.reconnectDelay = milliseconds;
return this;
}
/**
* Set the {@link MediaType media type} of the event data.
* <p>
* This information is mandatory. The default value is {@link MediaType#TEXT_PLAIN}.
* </p>
*
* @param mediaType {@link MediaType} of event data. Must not be {@code null}.
* @return updated builder instance.
* @throws NullPointerException in case the {@code mediaType} parameter is {@code null}.
*/
public Builder mediaType(final MediaType mediaType) {
if (mediaType == null) {
throw new NullPointerException(LocalizationMessages.OUT_EVENT_MEDIA_TYPE_NULL());
}
this.mediaType = mediaType;
return this;
}
/**
* Set comment string associated with the event.
*
* The comment will be serialized with the event, before event data are serialized. If the event
* does not contain any data, a separate "event" that contains only the comment will be sent.
* This information is optional, provided the event data are set.
* <p>
* Note that multiple invocations of this method result in a previous comment being replaced with a new one.
* To achieve multi-line comments, a multi-line comment string has to be used.
* </p>
*
* @param comment comment string.
* @return updated builder instance.
*/
public Builder comment(String comment) {
this.comment = comment;
return this;
}
/**
* Set event data and java type of event data.
*
* Type information will be used for {@link javax.ws.rs.ext.MessageBodyWriter} lookup.
* <p>
* Note that multiple invocations of this method result in previous even data being replaced with new one.
* </p>
*
* @param type java type of supplied data. Must not be {@code null}.
* @param data event data. Must not be {@code null}.
* @return updated builder instance.
* @throws NullPointerException in case either {@code type} or {@code data} parameter is {@code null}.
*/
public Builder data(Class type, Object data) {
if (data == null) {
throw new NullPointerException(LocalizationMessages.OUT_EVENT_DATA_NULL());
}
if (type == null) {
throw new NullPointerException(LocalizationMessages.OUT_EVENT_DATA_TYPE_NULL());
}
this.type = new GenericType(type);
this.data = data;
return this;
}
/**
* Set event data and a generic java type of event data.
*
* Type information will be used for {@link javax.ws.rs.ext.MessageBodyWriter} lookup.
* <p>
* Note that multiple invocations of this method result in previous even data being replaced with new one.
* </p>
*
* @param type generic type of supplied data. Must not be {@code null}.
* @param data event data. Must not be {@code null}.
* @return updated builder instance.
* @throws NullPointerException in case either {@code type} or {@code data} parameter is {@code null}.
* @since 2.3
*/
public Builder data(GenericType type, Object data) {
if (data == null) {
throw new NullPointerException(LocalizationMessages.OUT_EVENT_DATA_NULL());
}
if (type == null) {
throw new NullPointerException(LocalizationMessages.OUT_EVENT_DATA_TYPE_NULL());
}
this.type = type;
if (data instanceof GenericEntity) {
this.data = ((GenericEntity) data).getEntity();
} else {
this.data = data;
}
return this;
}
/**
* Set event data and java type of event data.
*
* This is a convenience method that derives the event data type information from the runtime type of
* the event data. The supplied event data may be represented as {@link javax.ws.rs.core.GenericEntity}.
* <p>
* Note that multiple invocations of this method result in previous even data being replaced with new one.
* </p>
*
* @param data event data. Must not be {@code null}.
* @return updated builder instance.
* @throws NullPointerException in case the {@code data} parameter is {@code null}.
* @since 2.3
*/
public Builder data(Object data) {
if (data == null) {
throw new NullPointerException(LocalizationMessages.OUT_EVENT_DATA_NULL());
}
return data(ReflectionHelper.genericTypeFor(data), data);
}
/**
* Build {@link OutboundEvent}.
* <p>
* There are two valid configurations:
* <ul>
* <li>if a {@link Builder#comment(String) comment} is set, all other parameters are optional.
* If event {@link Builder#data(Class, Object) data} and {@link Builder#mediaType(MediaType) media type} is set,
* event data will be serialized after the comment.</li>
* <li>if a {@link Builder#comment(String) comment} is not set, at least the event
* {@link Builder#data(Class, Object) data} must be set. All other parameters are optional.</li>
* </ul>
* </p>
*
* @return new {@link OutboundEvent} instance.
* @throws IllegalStateException when called with invalid configuration (neither a comment nor event data are set).
*/
public OutboundEvent build() {
if (comment == null && data == null && type == null) {
throw new IllegalStateException(LocalizationMessages.OUT_EVENT_NOT_BUILDABLE());
}
return new OutboundEvent(name, id, reconnectDelay, type, mediaType, data, comment);
}
}
/**
* Create new OutboundEvent with given properties.
*
* @param name event name (field name "event").
* @param id event id.
* @param reconnectDelay reconnection delay in milliseconds.
* @param type java type of events data.
* @param mediaType {@link MediaType} of events data.
* @param data events data.
* @param comment comment.
*/
OutboundEvent(final String name,
final String id,
final long reconnectDelay,
final GenericType type,
final MediaType mediaType,
final Object data,
final String comment) {
this.name = name;
this.comment = comment;
this.id = id;
this.reconnectDelay = reconnectDelay;
this.type = type;
this.mediaType = mediaType;
this.data = data;
}
/**
* Get event name.
* <p>
* This field is optional. If specified, will be send as a value of the SSE {@code "event"} field.
* </p>
*
* @return event name, or {@code null} if not set.
*/
public String getName() {
return name;
}
/**
* Get event identifier.
* <p>
* This field is optional. If specified, the value is send as a value of the SSE {@code "id"} field.
* </p>
*
* @return event identifier, or {@code null} if not set.
*/
public String getId() {
return id;
}
/**
* Get connection retry time in milliseconds the event receiver should wait before attempting to
* reconnect after a connection to the SSE source is lost.
* <p>
* This field is optional. If specified, the value is send as a value of the SSE {@code "retry"} field.
* </p>
*
* @return reconnection delay in milliseconds or {@link SseFeature#RECONNECT_NOT_SET} if no value has been set.
* @since 2.3
*/
public long getReconnectDelay() {
return reconnectDelay;
}
/**
* Check if the connection retry time has been set in the event.
*
* @return {@code true} if reconnection delay in milliseconds has been set in the event, {@code false} otherwise.
* @since 2.3
*/
public boolean isReconnectDelaySet() {
return reconnectDelay > SseFeature.RECONNECT_NOT_SET;
}
/**
* Get data type.
* <p>
* This information is used to select a proper {@link javax.ws.rs.ext.MessageBodyWriter} to be used for
* serializing the {@link #getData() event data}.
* </p>
*
* @return data type. May return {@code null}, if the event does not contain any data.
*/
public Class<?> getType() {
return type == null ? null : type.getRawType();
}
/**
* Get generic data type.
* <p>
* This information is used to select a proper {@link javax.ws.rs.ext.MessageBodyWriter} to be used for
* serializing the {@link #getData() event data}.
* </p>
*
* @return generic data type. May return {@code null}, if the event does not contain any data.
* @since 2.3
*/
public Type getGenericType() {
return type == null ? null : type.getType();
}
/**
* Get {@link MediaType media type} of the event data.
* <p>
* This information is used to a select proper {@link javax.ws.rs.ext.MessageBodyWriter} to be used for
* serializing the {@link #getData() event data}.
* </p>
*
* @return data {@link MediaType}.
*/
public MediaType getMediaType() {
return mediaType;
}
/**
* Get a comment string that accompanies the event.
* <p>
* If specified, the comment value is sent with the event as one or more SSE comment lines
* (depending on line breaks in the actual data string), before any actual event data are serialized.
* If the event instance does not contain any data, a separate "event" that contains only the comment
* will be sent. Comment information is optional, provided the event data are set.
* </p>
*
* @return comment associated with the event.
*/
public String getComment() {
return comment;
}
/**
* Get event data.
* <p>
* The event data, if specified, are serialized and sent as one or more SSE event {@code "data"} fields
* (depending on the line breaks in the actual serialized data content). The data are serialized
* using an available {@link javax.ws.rs.ext.MessageBodyWriter} that is selected based on the event
* {@link #getType() type}, {@link #getGenericType()} generic type} and {@link #getMediaType()} media type}.
* </p>
*
* @return event data. May return {@code null}, if the event does not contain any data.
*/
public Object getData() {
return data;
}
}