org.apache.pulsar.client.api.MessageId Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.pulsar.client.api;
import java.io.IOException;
import java.io.Serializable;
import org.apache.pulsar.client.internal.DefaultImplementation;
import org.apache.pulsar.common.classification.InterfaceAudience;
import org.apache.pulsar.common.classification.InterfaceStability;
/**
* Opaque unique identifier of a single message
*
* The MessageId can be used to reference a specific message, for example when acknowledging, without having
* to retain the message content in memory for an extended period of time.
*
*
Message ids are {@link Comparable} and a bigger message id will imply that a message was published "after"
* the other one.
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public interface MessageId extends Comparable, Serializable {
/**
* Serialize the message ID into a byte array.
*
* The serialized message id can be stored away and later get deserialized by
* using {@link #fromByteArray(byte[])}.
*/
byte[] toByteArray();
/**
* De-serialize a message id from a byte array.
*
* @param data
* byte array containing the serialized message id
* @return the de-serialized messageId object
* @throws IOException if the de-serialization fails
*/
static MessageId fromByteArray(byte[] data) throws IOException {
return DefaultImplementation.newMessageIdFromByteArray(data);
}
/**
* De-serialize a message id from a byte array with its topic
* information attached.
*
*
The topic information is needed when acknowledging a {@link MessageId} on
* a consumer that is consuming from multiple topics.
*
* @param data the byte array with the serialized message id
* @param topicName the topic name
* @return a {@link MessageId instance}
* @throws IOException if the de-serialization fails
*/
static MessageId fromByteArrayWithTopic(byte[] data, String topicName) throws IOException {
return DefaultImplementation.newMessageIdFromByteArrayWithTopic(data, topicName);
}
// CHECKSTYLE.OFF: ConstantName
/**
* MessageId that represents the oldest message available in the topic.
*/
MessageId earliest = DefaultImplementation.newMessageId(-1, -1, -1);
/**
* MessageId that represents the next message published in the topic.
*/
MessageId latest = DefaultImplementation.newMessageId(Long.MAX_VALUE, Long.MAX_VALUE, -1);
// CHECKSTYLE.ON: ConstantName
}