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Hazelcast IMDG Reference Manual 4.0.6

Welcome to the Hazelcast IMDG (In-Memory Data Grid) Reference Manual. This manual includes concepts, instructions and examples to guide you on how to use Hazelcast and build Hazelcast IMDG applications.

This reference manual mostly talks about the Hazelcast member and clients in Java language. Although, the core of Hazelcast IMDG is based on the Java programming language, it has the following clients and programming language APIs.

  • Java

  • .NET

  • C++

  • Node.js

  • Python

  • Go

We recommend you to learn the basics of Hazelcast IMDG using this manual first. Then, you can always get the client related resources/links in the Clients chapter.


This Reference Manual covers all editions of Hazelcast IMDG. Throughout this manual:

  • Hazelcast or Hazelcast IMDG refers to the open source edition of Hazelcast in-memory data grid middleware. Hazelcast is also the name of the company (Hazelcast, Inc.) providing the Hazelcast product.

  • Hazelcast IMDG Enterprise is a commercially licensed edition of Hazelcast IMDG which provides high-value enterprise features in addition to Hazelcast IMDG.

  • Hazelcast IMDG Enterprise HD is a commercially licensed edition of Hazelcast IMDG which provides High-Density (HD) Memory Store and Hot Restart Persistence features in addition to Hazelcast IMDG Enterprise.


Hazelcast IMDG and Hazelcast Reference Manual are free and provided under the Apache License, Version 2.0. Hazelcast IMDG Enterprise and Hazelcast IMDG Enterprise HD is commercially licensed by Hazelcast, Inc.

For more detailed information on licensing, see the License Questions appendix.


Hazelcast is a registered trademark of Hazelcast, Inc. All other trademarks in this manual are held by their respective owners.

Customer Support

Support for Hazelcast is provided via GitHub, Mail Group and StackOverflow.

For information on the commercial support for Hazelcast IMDG and Hazelcast IMDG Enterprise, see hazelcast.com.

Release Notes

See the Release Notes document for the new features, enhancements and fixes performed for each Hazelcast IMDG release.


You can contribute to the Hazelcast IMDG code, report a bug, or request an enhancement. See the following resources:

  • Developing with Git: Document that explains the branch mechanism of Hazelcast and how to request changes.

  • Hazelcast on GitHub: Hazelcast repository where the code is developed, issues and pull requests are managed.


Hazelcast partners with leading hardware and software technologies, system integrators, resellers and OEMs including Amazon Web Services, Vert.x, Azul Systems, C2B2. See the Partners page for the full list of and information on our partners.