Java Messaging

Open-source Java projects categorized as Messaging

Top 23 Java Messaging Projects

  • Apache Kafka

    Mirror of Apache Kafka

    Project mention: Scala DevInTraining looking to contribute to projects | | 2023-01-15
  • Apache RocketMQ

    Apache RocketMQ is a cloud native messaging and streaming platform, making it simple to build event-driven applications.

    Project mention: Storage Enhancements for Apache RocketMQ 5.0 in Stream Scenarios | | 2022-12-15

    Join the Apache RocketMQ community:

  • Sonar

    Write Clean Java Code. Always.. Sonar helps you commit clean code every time. With over 600 unique rules to find Java bugs, code smells & vulnerabilities, Sonar finds the issues while you focus on the work.

  • Apache Pulsar

    Apache Pulsar - distributed pub-sub messaging system

    Project mention: FLiP Stack Weekly for 15-Jan-2023 | | 2023-01-15

    Pulsar Shell (

  • Aeron

    Efficient reliable UDP unicast, UDP multicast, and IPC message transport

    Project mention: Aeron: Efficient reliable UDP unicast, UDP multicast, and IPC message transport | | 2023-01-07
  • Apache Camel

    Apache Camel is an open source integration framework that empowers you to quickly and easily integrate various systems consuming or producing data.

    Project mention: Can I continuously write to a CSV file with a python script while a Java application is continuously reading from it? | | 2023-02-01

    Since you're writing a Java app to consume this, I highly recommend Apache Camel to do the consuming of messages for it. You can trivially aim it at file systems, message queues, databases, web services and all manner of other sources to grab your data for you, and you can change your mind about what that source is, without having to rewrite most of your client code.

  • strimzi-kafka-operator

    Apache Kafka® running on Kubernetes

    Project mention: Am I wrong for avoiding helm completely? | | 2022-10-29

    Strimzi is an operator for deploying Kafka in K8s, and makes extensive use of CRs. E.g.,

  • ChatKit for Android

    Android library. Flexible components for chat UI implementation with flexible possibilities for styling, customizing and data management. Made by Stfalcon

  • InfluxDB

    Build time-series-based applications quickly and at scale.. InfluxDB is the Time Series Platform where developers build real-time applications for analytics, IoT and cloud-native services. Easy to start, it is available in the cloud or on-premises.

  • signal-cli

    signal-cli provides an unofficial commandline and dbus interface for signalapp/libsignal-service-java

    Project mention: Is it possible to create Signal chat bot? | | 2023-01-12
  • Smack

    A modular and portable open source XMPP client library written in Java for Android and Java (SE) VMs

    Project mention: Zoom: Remote Code Execution with XMPP Stanza Smuggling | | 2022-05-24

    I don't see any opportunity not to block when calling "next"

  • JeroMQ

    Pure Java ZeroMQ

  • Apache ActiveMQ

    Mirror of Apache ActiveMQ

    Project mention: How exactly do events work? | | 2022-11-20

    If you just want to use events in your software, use whatever native event model your language supports, or a popular separate component. If you want to develop your own message queue/event system, you could for example look at the ActiveMQ source.

  • RabbitMQ Java client

    RabbitMQ Java client

  • MBassador

    Powerful event-bus optimized for high throughput in multi-threaded applications. Features: Sync and Async event publication, weak/strong references, event filtering, annotation driven

  • Nakadi

    A distributed event bus that implements a RESTful API abstraction on top of Kafka-like queues

  • hivemq-community-edition

    HiveMQ CE is a Java-based open source MQTT broker that fully supports MQTT 3.x and MQTT 5. It is the foundation of the HiveMQ Enterprise Connectivity and Messaging Platform

  • Apache ActiveMQ Artemis

    Mirror of Apache ActiveMQ Artemis

  • Hermes

    Fast and reliable message broker built on top of Kafka. (by allegro)

    Project mention: Got fed up with AMQP, so I wrote a HTTP message broker on top of RabbitMQ | | 2022-03-27

    Let's draw some parallels in the Kafka ecosystem, in which there are Confluent REST Proxy and Hermes by Allegro. You could say that since Kafka uses a binary protocol over TCP, both of these projects are "moot and useless". Despite that, Allegro aka the Poland's Amazon still maintains that project and uses it in production as a means of HTTP-based communication between their 700+ microservices arguing that it makes their development process easier, since it allows them to abstract away the intricacies of Kafka and use plain HTTP instead.

  • threema-android

    Threema App for Android.

    Project mention: Official /r/rust "Who's Hiring" thread for job-seekers and job-offerers [Rust 1.67] | | 2023-01-28

    DESCRIPTION: Threema is one of the most successful Swiss app developers and offers secure chat solutions for both individuals and organizations. We have been committed to security and privacy protection since 2012. Our messenger, which is used by over 10 million people, is open source and has been audited by independent companies multiple times. Our company is characterized by flat hierarchies, a relaxed work environment, strong team spirit, and sustainability.

  • countly-sdk-android

    Countly Product Analytics Android SDK

  • NATS client

    Java client for NATS

  • parallel-consumer

    Parallel Apache Kafka client wrapper with per message ACK, client side queueing, a simpler consumer/producer API with key concurrency and extendable non-blocking IO processing.

    Project mention: Optimizing Kafka Producers and Consumers | | 2023-01-31

    Hi everyone, my name is Daniel and I run a website called Rock the JVM [1]. It's a popular site and blog for Scala, and we've recently started to create guides and materials for other libraries and languages. This video is about - maximizing producer throughput - minimizing producer latency - running multiple consumers vs number of partitions, analyzing parallelism - parallel consumers [2] for 1000x perf increase vs 1x single-threaded consumer I also have written forms of all videos as long-form blog posts, and you can find the written guide here [3]. I hope you like it - let me know if you need anything or have any questions! [1] [2] [3]

  • Citrus

    Framework for automated integration tests with focus on messaging integration

    Project mention: Best tool for automated API e2e testing | | 2022-10-27

    There is such a one, which does fit these requirements consistently and doesn't try to embrace everything badly. And guess what it's also compliant with Cucumber and doesn't try to reivent thee wheel.

  • tigase-server

    (M) Highly optimized, extremely modular and very flexible XMPP/Jabber server

    Project mention: What's the best xmpp server? | | 2022-10-24

    There is also Tigase XMPP Server (, We try to make the default configuration as close as possible to the compatibility. There is also nice web installer to help setting everything up.

  • SaaSHub

    SaaSHub - Software Alternatives and Reviews. SaaSHub helps you find the best software and product alternatives

NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020). The latest post mention was on 2023-02-01.

Java Messaging related posts


What are some of the best open-source Messaging projects in Java? This list will help you:

Project Stars
1 Apache Kafka 24,045
2 Apache RocketMQ 18,639
3 Apache Pulsar 12,235
4 Aeron 6,329
5 Apache Camel 4,700
6 strimzi-kafka-operator 3,657
7 ChatKit for Android 3,588
8 signal-cli 2,523
9 Smack 2,321
10 JeroMQ 2,182
11 Apache ActiveMQ 2,126
12 RabbitMQ Java client 1,130
13 MBassador 930
14 Nakadi 871
15 hivemq-community-edition 871
16 Apache ActiveMQ Artemis 833
17 Hermes 743
18 threema-android 705
19 countly-sdk-android 649
20 NATS client 455
21 parallel-consumer 427
22 Citrus 376
23 tigase-server 267
SaaSHub - Software Alternatives and Reviews
SaaSHub helps you find the best software and product alternatives