The correct answer is C. publish().
The publish() method is used to publish messages to a topic. It takes a topic name and a message as arguments. The message can be any object that implements the Message interface.
The client() method is used to create a client for a topic. It takes a topic name as an argument. The client can be used to subscribe to messages on the topic, publish messages to the topic, and acknlowledge messages.
The server() method is used to create a server for a topic. It takes a topic name and a port number as arguments. The server can be used to receive messages from clients on the topic, and publish messages to the topic.
The batch() method is used to batch messages together before publishing them. It takes a list of messages as an argument. The messages are batched together and published as a single message.
Here is an example of how to use the publish() method:
“`
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
public class Publisher {
public static void main(String[] args) throws Exception {
// Create a connection factory
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
factory.setPort(5672);
// Create a connection
Connection connection = factory.newConnection();
// Create a channel
Channel channel = connection.createChannel();
// Publish a message
channel.basicPublish("topic/foo", "", null, "Hello, world!");
// Close the channel and connection
channel.close();
connection.close();
}
}
“`
This code will publish a message with the body “Hello, world!” to the topic “topic/foo”.