Message Actions API for Java SDK

Breaking changes in v9.0.0

PubNub Java SDK version 9.0.0 unifies the codebases for Java and Kotlin SDKs, introduces a new way of instantiating the PubNub client, and changes asynchronous API callbacks and emitted status events. These changes can impact applications built with previous versions (< 9.0.0) of the Java SDK.

For more details about what has changed, refer to Java/Kotlin SDK migration guide.

Use message actions to add or remove metadata on published messages. Common uses include receipts and reactions. Clients subscribe to a channel to receive message action events. Clients can also fetch past message actions from Message Persistence, either on demand or when fetching original messages.

Reactions

"Message Reactions" is a specific application of the Message Actions API for emoji or social reactions.

Message Actions vs. Message Reactions

Message Actions is the flexible, low-level API for adding any metadata to messages (read receipts, delivery confirmations, custom data), while Message Reactions specifically refers to using Message Actions for emoji/social reactions.

In PubNub Core and Chat SDKs, the same underlying Message Actions API is referred to as Message Reactions when used for emoji reactions - it's the same functionality, just different terminology depending on the use case.

Add message action

Requires Message Persistence

Enable Message Persistence for your key in the Admin Portal as described in the support article.

Add an action to a published message. The response includes the added action.

Method(s)

Use this Java method:

this.pubnub.addMessageAction()
    .channel(String)
    .messageAction(PNMessageAction);

* required

Parameter	Description
channel * Type: String	Channel name to add the message action to.
messageAction * Type: PNMessageAction	Message action payload (type, value, message timetoken).
async * Type: Consumer<Result>	Callback of type PNAddMessageActionResult.

Sample code

Reference code

This example is a self-contained code snippet ready to be run. It includes necessary imports and executes methods with console logging. Use it as a reference when working with other examples in this document.

Returns

The addMessageAction() operation returns a PNAddMessageActionResult:

Method	Description
getType() Type: String	Message action type.
getValue() Type: String	Message action value.
getUuid() Type: String	Publisher of the message action.
getActionTimetoken() Type: Long	Timestamp when the message action was created.
getMessageTimetoken() Type: Long	Timestamp when the message was created that the action belongs to.

PNMessageAction

Method	Description
setType() Type: String	Message action type.
setValue() Type: String	Message action value.
setMessageTimetoken() Type: Long	Timetoken of the target message.

Remove message action

Requires Message Persistence

Enable Message Persistence for your key in the Admin Portal as described in the support article.

Remove a previously added action from a published message. The response is empty.

Method(s)

Use this Java method:

this.pubnub.removeMessageAction()
    .channel(String)
    .messageTimetoken(Long)
    .actionTimetoken(Long);

* required

Parameter	Description
channel * Type: String	Channel name to remove the message action from.
messageTimetoken * Type: Long	Timetoken of the target message.
actionTimetoken * Type: Long	Timetoken of the message action to remove.
async * Type: Consumer<Result>	Callback of type PNRemoveMessageActionResult.

Sample code

Returns

The removeMessageAction() operation returns no actionable data.

Get message actions

Requires Message Persistence

Enable Message Persistence for your key in the Admin Portal as described in the support article.

Get a list of message actions in a channel. The response sorts actions by the action timetoken in ascending order.

Truncated response

The number of message actions in the response may be truncated when internal limits are hit. If the response is truncated, a more property is returned with additional parameters. Send iterative calls to Message Persistence, adjusting the parameters to fetch more message actions.

Method(s)

Use this Java method:

this.pubnub.getMessageActions()
    .channel(String)
    .start(Long)
    .end(Long)
    .limit(Integer);

* required

Parameter	Description
channel * Type: String Default: n/a	Channel name to list message actions for.
start Type: Long Default: n/a	Message action timetoken for the start of the range (exclusive).
end Type: Long Default: n/a	Message action timetoken for the end of the range (inclusive).
limit Type: Integer Default: 100	Maximum number of actions to return. Default/Maximum is 100.
async * Type: Consumer<Result> Default: n/a	Callback of type PNGetMessageActionsResult.

Sample code

Returns

The getMessageActions() operation returns a list of PNGetMessageActionsResult objects:

Method	Description
getType() Type: String	Message action type.
getValue() Type: String	Message action value.
getUuid() Type: String	Publisher of the message action.
getActionTimetoken() Type: Long	Timestamp when the message action was created.
getMessageTimetoken() Type: Long	Timestamp when the message was created that the action belongs to.

Other examples

Fetch messages with paging